Cyrus the Great establishes the Achaemenid Empire

WEBVTT
Kind: captions
Language: en

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- [Instructor] As we enter
into the sixth century BCE,

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the dominant power in the region

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that we now refer to as Iran,
it was the Median Empire.

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And the Median Empire...

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I'll draw the rough
border right over here.

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Was something like that.

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And you can see the dominant region

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of Media right over here.

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But, by the middle of that century,

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they are going to be overthrown.

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They're going to be overthrown

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by one of their subject kingdoms.

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And that is the Persians.

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And so, right over here on this map,

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it's called Persis, but that
region is called Pars or Fars.

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And, even today in modern Iran,
that region is called Fars.

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And the king of Pars was Cyrus the Great.

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And, in 550/549 BCE,
he's able to overthrow

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the Median emperor, who
happens to be his grandfather,

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and then he establishes what history views

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as the first real Persian empire.

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And the whole reason why we
even call it a Persian empire

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is because Cyrus the Great was from Pars.

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Persian is really
referring to the idea that

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the ruler, the dynasty
that gets established,

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was coming from Pars.

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It turns out, and I talk
about in other videos,

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the Persians did not refer
to themselves as Persians.

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They viewed themselves
more as the Aryan people.

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In a lot of ways, Eran or
Iran or Arianum of Asia,

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these types of words are
more accurate for how

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the Persians viewed themselves.

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But, needless to say,
in 549, Cyrus the Great

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is able to conquer the Median
Empire and he keeps going.

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And what he establishes,
this empire, this dynasty,

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is called the Achaemednid Dynasty.

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And you might wonder

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why is it called the Achaemenid Dynasty,

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instead of, say, the Cyrid Dynasty?

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And that's because Cyrus claims

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descendant from Achaemenes.

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He is part of that family.

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Achaemenes is this
semi-legendary patriarch of it

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that lived 100, 150 years
before Cyrus the Great.

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And so, I will draw a dotted
line from Achaemenes to Cyrus.

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And Cyrus then goes on.

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So, he conquers the Median Empire,

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then he goes on to conquer

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several of the major empires of that time.

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In the mid-540's BCE....

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So, we are right around there.

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He conquers the Lydian
Empire, right over there,

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which is on the western half of

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the Anatolian Peninsula
in modern day Turkey.

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And then, he sets his sight
on the Neo-Babylonian Empire.

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And, in 539, he's able to conquer
the Neo-Babylonian Empire.

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And, from a Biblical
perspective, that's relevant.

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Because, when he takes Babylon,

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he frees the Jews from
the Babylonian captivity

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and he resettles them in Jerusalem.

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And he works with them to
rebuild the city of Jerusalem

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and, especially, Solomon's Temple,

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which is now called the Second
Temple on the Temple Mount.

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And Cyrus the Great is viewed by history

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as one of the great rulers of all time.

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Often referred to as a model ruler.

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Someone who really takes the

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interest of his people at heart.

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So, Cyrus was able to conquer

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a lot of what you see here in green,

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but not all of it.

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And, especially, he was
not able to get to Egypt.

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That would be left to his son, Cambyses.

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So, in 530, Cyrus dies
and Cambyses takes over.

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And, just so you read how
I made this timeline...

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And I made this timeline, really,

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to help myself understand the various

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shahanshahs or king of kings of Iran.

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So, Cyrus the Great was the
shahanshah, king of kings.

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And then, Cambyses II was the next one.

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Is that, this timeline up here,

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this shows who was in charge.

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So, you see from 550/549
all the way up to 530,

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I have it yellow and that's
'cause Cyrus the Great

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was in charge of what is
called the Achaemenid Empire

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or, I guess you could say, this
first great Persian empire.

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What I have down here is the
best information I could find

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on the lifespans of these people.

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And, when I have these dotted
lines at the beginning,

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that's when it's unclear
when these people were born.

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So, there's different accounts that

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Cyrus the Great might
have been born in 575 BCE.

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He might have been born closer to 600 BCE.

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And so, that's why I
have these dotted lines.

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Similarly, we don't know exactly
when Cambyses II was born,

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but we do know that he
took control in 530 BCE.

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And so, that's why you see Cambyses,

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you see this line right
over here turn blue.

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And, actually Cambyses
ends up dying in 522.

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So, actually, this should be like that.

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There you go.

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He ends up dying in 522.

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But, before he dies in 522,

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he is able to conquer Egypt in 525 BCE.

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So, right around there.

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And you can imagine that,
while he's conquering Egypt...

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Let me keep drawing this family tree.

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So, now we have Cambyses II.

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He goes off, makes his
real goal to conquer Egypt.

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And that's a big deal.

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Remember, this is ending
thousands of years

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of the rule by the native pharaohs.

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These now foreign rulers start

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calling themselves the
pharaohs of Egypt, as well.

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Egypt becomes part of the

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Persian Empire because of Cambyses,

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but you can imagine with the
shahanshah, the king of kings,

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off and doing conquest in Egypt,

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it leaves a little power vacuum

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back in the center of the empire.

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And this is when things
get a little bit sketchy.

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So, Cyrus does have another son.

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Th other son is called Bardiya.

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So, let me write this down.

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So, there's another son called Bardiya.

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And then, there's this other
character known as Darius,

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soon to be known as Darius the Great.

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And Darius is not a direct
descendant of Cyrus the Great,

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but he is part of his family.

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He's a distant relative.

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He is part of the Achaemenid dynasty.

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He claims descendant from Achamenes.

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And he was the lance-bearer
for Cambyses II.

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So, while Cambyses is

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out here in Egypt leaving
that power vacuum,

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someone who claims to be Bardiya

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takes control of the empire

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or is trying to take
control of the empire.

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Now, some accounts say that
this is really Bardiya.

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This is really the other
son of Cyrus the Great

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and so there would be some
legitimate claim to the throne,

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but there's other claims,
especially the ones

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that Darius was later able to spread,

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that, no, this was not the real Bardiya.

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That this was a fake Bardiya.

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That the real Bardiya had actually

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been killed by Cambyses II before

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and that this person
proposing to be Bardiya

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was this fake usurper,

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this Zoroastrian priest named Gaumata.

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And, once Cambyses, on his way....

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He's trying to come back in
order to reclaim the throne

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or in order to get rid of this usurper,

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whether it was the real Bardiya or not.

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But, on the way, he dies,

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once again, under dubious circumstances.

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Cyrus the Great, how he died, not clear.

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Cambyses II also dies under
dubious circumstances.

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And then this Bardiya actually

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becomes the shahanshah for real.

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He obviously has claims to
it while Cambyses is there,

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but, once Cambyses dies,
he is the shaanshah.

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Well, Darius doesn't like this.

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He has his own imperial ambitions.

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He gets some other
nobility together and says,

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"No, no, no, this Bardiya
isn't the real Bardiya.

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He's a usurper.

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Let's go kill that guy."

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And so, they kill him and then...

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It's an interesting story.

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Herodotus has a fairly dubious account

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of how Darius was able to
convince the other noble people

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why he should be the
shahanshah, the emperor.

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But they are able to get rid of Bardiya.

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We still do not know whether
it was the real Bardiya

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or whether it was the fake Bardiya.

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But then, Darius takes power in 522 BCE.

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And he's known as Darius the Great

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because he continues to spread,

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continues to conquer more and
more for the Persian Empire.

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And this map, right over here,

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this is the Persian Empire

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in 500 BCE under Darius the Great.

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It's near its maximum extent.

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And it's a pretty incredible empire.

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It's worth noting....

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And it's big by any
stretch of the imagination.

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But it's at this time the population

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is on the order of 50 million people.

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And, based on the accounts that I've seen,

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that's almost half of the
world population at that time.

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No empire in history,
as far as we can tell,

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has ever had such a large fraction

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of the world's population
under its control.

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And so, that gives you a sense
of, I guess you could say,

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how great or how large an empire this was.

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Now Darius the Great, he is also famous,

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especially from a Greek perspective,

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for going after the Greeks.

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You had these Greek revolts in these towns

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on the west coast of
the Anatolian Peninsula.

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They revolted against
their Persian overlords,

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I guess you could say.

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And they did that with
the help of the Athenians.

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And so, Darius didn't like this.

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In the 490's, he starts
going after the Athenians.

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This is the beginning of
the Greco-Persian Wars.

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He is unsuccessful.

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He dies in the 480's and then his son...

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This is actually a relief of

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Darius the Great right
over here from Persepolis.

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And then, his son continues
to try to take over

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in the Second Greco-Persian Wars.

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And he, too, is unsuccessful.

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But, it's worth noting, a lot
of this history that we get,

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especially of Cyrus the Great

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and the early Persian shahanshas,

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the history we get is from the Greeks.

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So, it's worth taking it
with a great grain of salt,

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because, as you can see, they were rivals.

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And to say rivals is a little
bit unfair to the Persians,

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because the Greeks were more of

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a thorn in the side of a large empire.

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The Greeks were this group of city-states.

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They weren't even a unified empire.

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While you had here the Persian Empire

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controls almost half of
the world's population.

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So, the Greeks were more
of a thorn in the side,

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but we get our history from them

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or a lot of our history from them.

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So, we get their account of things.

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Now, once you have Xerxes,

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then, after Xerxes, you have
Artaxerxes, right over here.

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And then, you have a little bit of a

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squabble for the throne
and then Darius II.

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There's one thing that you see

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over 200 years of Achaemenid rule

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is that most people,
after Darius the Great,

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are named either Xerxes,
Artaxerxes, Darius II, III, IV,

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or Darius II or III, at least, not fourth.

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Artaxerxes II, Artaxerxes III.

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So, it can get a little confusing.

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But the reason why I
even did this for myself,

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to see when all these people
lived and when they ruled,

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is to have a good sense
of what was going on

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and how Darius II lived
at a different time

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than, for example, Darius
I, or Darius the Great.

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The other thing worth mentioning,

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'cause you'll hear this
in various history classes

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when you talk about the Persian Empire,

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is the great cities of the Persian Empire.

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Cyrus the Great, he
establishes the capital

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at Pasargadae right over here.

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You have Cambyses establishes
a capital at Susa.

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Susa is one end of the great royal highway

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that goes from Sardis all the
way to Susa right over there.

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You have Darius the Great
establish a capital at Persepolis.

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And that's the Greek name for it,

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literally referring to Persian city.

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And this is a relief from
Persepolis right over here.

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Now, the end of the Achaemenid Dynasty

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comes when that famous
thorn in the side, Greece,

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actually unifies under Philip of Macedon.

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Here, we're talking about the

00:12:07.989 --> 00:12:11.160
early to mid-fourth century BCE.

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And his son, Alexander,

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becomes this great conqueror,
Alexander the Great.

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And he's able to conquer
the entire Persian Empire,

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famously taking it away from Darius III.

00:12:20.861 --> 00:12:23.158
We talk about that in another video

00:12:23.158 --> 00:12:25.740
or in several videos in some detail.

00:12:25.740 --> 00:12:28.259
But, Alexander the
Great, he has this vision

00:12:28.259 --> 00:12:30.281
of one nation of these people.

00:12:30.281 --> 00:12:32.493
Their cultures mixing together.

00:12:32.493 --> 00:12:34.213
And there's a significant
amount of cultural mix

00:12:34.213 --> 00:12:36.385
between the Greeks and the Persians.

00:12:36.385 --> 00:12:40.067
But then, Alexander dies
and his empire is split.

00:12:40.067 --> 00:12:42.727
But most of the Persian Empire

00:12:42.727 --> 00:12:45.644
goes under the control of Seleucus,

00:12:47.317 --> 00:12:48.834
who's one of Alexander's generals,

00:12:48.834 --> 00:12:50.145
and then you have the Seleucid Empire,

00:12:50.145 --> 00:12:52.317
which is really foreign rule of Persia.

00:12:52.317 --> 00:12:54.327
And that will continue for a while.

00:12:54.327 --> 00:12:56.334
Until, eventually, the Parthians,

00:12:56.334 --> 00:12:57.973
which is, once again, another

00:12:57.973 --> 00:13:01.291
state or region of the Persian Empire,

00:13:01.291 --> 00:13:03.624
takes control to establish
the Parthian Empire,

00:13:03.624 --> 00:13:06.121
which is one of the rivals to Rome.

00:13:06.121 --> 00:13:07.021
It's worth mentioning,

00:13:07.021 --> 00:13:09.474
and I mention this in the
video on ancient Persia,

00:13:09.474 --> 00:13:10.864
that, under Persian rule, and Cyrus

00:13:10.864 --> 00:13:12.709
and the various shahanshahs

00:13:12.709 --> 00:13:14.919
were famous for delegating
their authority.

00:13:14.919 --> 00:13:16.433
When you have such a large empire,

00:13:16.433 --> 00:13:18.315
you can't control all of it yourself.

00:13:18.315 --> 00:13:20.362
So, each of these regions had their own,

00:13:20.362 --> 00:13:22.162
I guess you could say, governors.

00:13:22.162 --> 00:13:24.129
And those governors were called satraps

00:13:24.129 --> 00:13:26.175
and the regions were called satrapies.

00:13:26.175 --> 00:13:27.484
Anyway, I will leave you there.

00:13:27.484 --> 00:13:28.793
Oh, and the other thing that

00:13:28.793 --> 00:13:30.841
Cyrus the Great is really known for,

00:13:30.841 --> 00:13:33.257
is the spread of the Zoroastrian faith.

00:13:33.257 --> 00:13:36.289
We talk about the Zoroastrian
faith in other videos.

00:13:36.289 --> 00:13:39.645
And Zarathustra, who
is kind of the prophet

00:13:39.645 --> 00:13:41.037
of the Zoroastrian faith,

00:13:41.037 --> 00:13:43.369
he lived someplace between 1500 BCE

00:13:43.369 --> 00:13:46.033
and might have even lived
shortly right before,

00:13:46.033 --> 00:13:47.886
almost near the time of Cyrus the Great.

00:13:47.886 --> 00:13:49.605
But it was really Cyrus
the Great who helps

00:13:49.605 --> 00:13:52.272
spread this great ancient faith.


Share your career story with Khan Academy for our new series

WEBVTT
Kind: captions
Language: en

00:00:00.524 --> 00:00:03.142
- Hi, I'm Sal Kahn, founder
of the Kahn Academy.

00:00:03.142 --> 00:00:04.902
I'm here to invite you to participate in

00:00:04.902 --> 00:00:08.538
an exciting project that
we have around career.

00:00:08.538 --> 00:00:10.772
Our mission statement,
as a not for profit,

00:00:10.772 --> 00:00:12.522
is to provide a free world-class education

00:00:12.522 --> 00:00:14.538
for anyone anywhere.

00:00:14.538 --> 00:00:17.629
Part of that is help people
navigate their careers.

00:00:17.629 --> 00:00:19.036
What do they want to major in?

00:00:19.036 --> 00:00:20.347
What jobs do they want to pursue?

00:00:20.347 --> 00:00:22.568
What are the implications on their life

00:00:22.568 --> 00:00:24.429
in terms of finance?

00:00:24.429 --> 00:00:26.149
This is part of a
partnership that we're doing

00:00:26.149 --> 00:00:27.485
with Bank of America.

00:00:27.485 --> 00:00:29.690
We're looking for people
in all walks of life,

00:00:29.690 --> 00:00:32.068
in all sorts of careers, who are willing

00:00:32.068 --> 00:00:34.660
to be videotaped and
answer questions about

00:00:34.660 --> 00:00:36.125
how they chose their careers,

00:00:36.125 --> 00:00:39.540
the good, the bad, money questions,

00:00:39.540 --> 00:00:41.443
how they budget, how much they make.

00:00:41.443 --> 00:00:42.836
- Hi, my name is Tamillia James,

00:00:42.836 --> 00:00:44.648
and I'm a high school guidance counselor.

00:00:44.648 --> 00:00:45.481
- My name's Eddie.

00:00:45.481 --> 00:00:47.433
I'm 26 years old, and I
work as a health coach.

00:00:47.433 --> 00:00:48.704
- My name is Emmie Kelsey.

00:00:48.704 --> 00:00:49.742
I'm 22 years old.

00:00:49.742 --> 00:00:51.761
I work as a business associate

00:00:51.761 --> 00:00:53.624
at an indoor vertical farming startup.

00:00:53.624 --> 00:00:54.743
- My name's Anna Nelson.

00:00:54.743 --> 00:00:56.338
I'm 28 years old.

00:00:56.338 --> 00:00:58.468
I'm an instructional
designer at a startup.

00:00:58.468 --> 00:01:01.039
- A health coach is a
number of different things,

00:01:01.039 --> 00:01:04.291
depending on the individual
that we come across.

00:01:04.291 --> 00:01:07.236
It can be a motivational interviewer.

00:01:07.236 --> 00:01:09.049
It can be an exercise partner.

00:01:09.049 --> 00:01:10.397
- We're not like a traditional company

00:01:10.397 --> 00:01:12.373
where I have an immediate supervisor

00:01:12.373 --> 00:01:14.168
that I get all of my work from.

00:01:14.168 --> 00:01:16.446
- Currently I make $90,000 a year.

00:01:16.446 --> 00:01:18.929
- When I first started as a
high school guidance counselor

00:01:18.929 --> 00:01:20.802
and I was making $50,000.

00:01:20.802 --> 00:01:24.264
- When I finally left graduate school,

00:01:24.264 --> 00:01:26.889
I had something like $72,000 in debt.

00:01:26.889 --> 00:01:28.312
- If you're interested in participating,

00:01:28.312 --> 00:01:30.894
you'd like to be on
camera, answering questions

00:01:30.894 --> 00:01:33.119
about where you are in your career,

00:01:33.119 --> 00:01:36.215
questions about finance,
decisions that you've made,

00:01:36.215 --> 00:01:38.420
please click on the link below

00:01:38.420 --> 00:01:40.308
and submit either a short video,

00:01:40.308 --> 00:01:44.061
or a short written piece
about what you do and why.

00:01:44.061 --> 00:01:47.144
(light upbeat music)


Overview of ancient Persia

WEBVTT
Kind: captions
Language: en

00:00:00.114 --> 00:00:01.545
- [Instructor] We're
going to do in this video

00:00:01.545 --> 00:00:03.955
is have an overview of one
of the greatest empires

00:00:03.955 --> 00:00:06.647
and really civilizations of
not only the ancient world,

00:00:06.647 --> 00:00:09.730
but of the world, and that is Persia.

00:00:10.573 --> 00:00:13.876
And we see a map here, this
is the extent of the Persian

00:00:13.876 --> 00:00:17.553
empire at around 500 B.C.E.
under Darius the Great

00:00:17.553 --> 00:00:20.866
and in future videos we'll
talk more about Cyrus the Great

00:00:20.866 --> 00:00:23.888
and Darius the Great and
the various Shah and Shahs

00:00:23.888 --> 00:00:26.718
King of Kings of the Persian
empire, but you can see

00:00:26.718 --> 00:00:28.640
it was a massive empire.

00:00:28.640 --> 00:00:32.123
Not only did it contain
modern Iran which is really

00:00:32.123 --> 00:00:35.758
the heart of the Persian
empire, but much of the modern

00:00:35.758 --> 00:00:38.876
Middle East including
Turkey, you have Egypt here

00:00:38.876 --> 00:00:41.318
we go into central Asia
and also Afghanistan

00:00:41.318 --> 00:00:43.758
and even parts of Pakistan.

00:00:43.758 --> 00:00:47.029
But before talking more
about how it was established

00:00:47.029 --> 00:00:50.357
and who established it, I'm
gonna dig down a little bit

00:00:50.357 --> 00:00:55.093
into the word "Persia"
because just as the ancient

00:00:55.093 --> 00:00:58.608
Greeks did not refer to
where they lived as Greece

00:00:58.608 --> 00:01:02.617
that is a Latin idea of calling it Greece,

00:01:02.617 --> 00:01:07.124
the Greeks referred to where
they lived as "Hellas",

00:01:07.124 --> 00:01:08.883
it turns out that the
Persians did not refer

00:01:08.883 --> 00:01:11.296
to where they lived as "Persia".

00:01:11.296 --> 00:01:15.434
Their terms are actually
much closer to ideas around

00:01:15.434 --> 00:01:20.058
land of the Aryans, so
there's, based on my research,

00:01:20.058 --> 00:01:23.808
ideas like Aryan-Vega
and Aran-Shah and Aran.

00:01:25.659 --> 00:01:28.489
So it actually turns out
that the modern name of the

00:01:28.489 --> 00:01:33.281
country, the modern word Iran
is probably more appropriate

00:01:33.281 --> 00:01:37.503
or in some ways closer to
what the region has always

00:01:37.503 --> 00:01:41.066
called itself, what the
Iranians or the Persians have

00:01:41.066 --> 00:01:45.233
always called themselves,
and called where they lived.

00:01:46.434 --> 00:01:50.241
They referred to themselves
as the Aryans and where

00:01:50.241 --> 00:01:54.989
they lived as the Aryanan-Vega
or Aran, or Aran-Shah

00:01:54.989 --> 00:01:59.445
or some version of that and
the modern version is Iran.

00:01:59.445 --> 00:02:00.754
Now, with that said, you might say,

00:02:00.754 --> 00:02:04.024
"Well, why did the Greeks call it Persia?"

00:02:04.024 --> 00:02:07.630
Well, the Persian empire what
we consider to be the first

00:02:07.630 --> 00:02:11.227
true Persian empire is the
Achaemenid empire, and we'll

00:02:11.227 --> 00:02:14.338
talk in a second why do we
call it even the Achaemenid,

00:02:14.338 --> 00:02:18.178
but the Achaemenid empire
emerges from a region

00:02:18.178 --> 00:02:22.384
of Persia, I guess we can
say, that in this map is

00:02:22.384 --> 00:02:26.148
referred to as Persus,
but other names for it are

00:02:26.148 --> 00:02:29.789
Pars, and even in modern
Iran there's a region called

00:02:29.789 --> 00:02:33.122
Fars which coincides very close with it.

00:02:33.975 --> 00:02:38.142
And since the leaders of the
Persian empire, and especially

00:02:39.086 --> 00:02:43.253
Cyrus the Great, emerged from
this region, they called them

00:02:44.651 --> 00:02:48.701
the Persians and it was the
"Persian" empire that emerges

00:02:48.701 --> 00:02:52.463
from this region which you
might wanna call Pars, Fars.

00:02:52.463 --> 00:02:55.241
Fars especially comes from
Arabic where they don't

00:02:55.241 --> 00:02:59.408
have the P sound, but Pars or
Persus or whatever you wanna

00:03:00.347 --> 00:03:04.514
call it, and that's why it
was called the Persian empire.

00:03:05.388 --> 00:03:09.476
Now, it wasn't the first
empire in that region.

00:03:09.476 --> 00:03:12.418
Before the Persian empire
gets established or what

00:03:12.418 --> 00:03:15.576
we associate with the Persian
or the Achaemenid empire

00:03:15.576 --> 00:03:19.166
of Cyrus the Great, much
of this region of where we

00:03:19.166 --> 00:03:21.916
call modern day Iran was
controlled by the Medians,

00:03:21.916 --> 00:03:26.849
and you can see Media is
this region right over here.

00:03:26.849 --> 00:03:31.644
And it was Cyrus the Great
that in 549, some accounts

00:03:31.644 --> 00:03:35.811
say 550 B.C.E., is able to
overthrow the Median emperor

00:03:37.001 --> 00:03:39.733
who happens to be his grandfather.

00:03:39.733 --> 00:03:44.342
And that is the really dawn
of the Achaemenid dynasty.

00:03:44.342 --> 00:03:46.427
Now the next question
and this was established,

00:03:46.427 --> 00:03:49.212
let me write this down, this
was established by Cyrus

00:03:49.212 --> 00:03:53.379
the Great, he was Cyrus the II
but he became Cyrus the Great

00:03:54.979 --> 00:03:58.210
because he was able to break
out and overthrow the Medians

00:03:58.210 --> 00:04:01.043
and establish this massive empire.

00:04:01.971 --> 00:04:04.345
And the reason why it's
called the Achaemenid empire

00:04:04.345 --> 00:04:08.512
not the Cyrid empire, is
that Cyrus claims to be from

00:04:12.442 --> 00:04:16.568
the family of the patriarch
Achaemenis and a lot of

00:04:16.568 --> 00:04:18.932
these names, these are
come from Greek accounts so

00:04:18.932 --> 00:04:21.543
that's why they sound a
little bit more Greek.

00:04:21.543 --> 00:04:26.455
But Achaemenis is a semi-legendary
figure that, we're not

00:04:26.455 --> 00:04:29.807
sure exactly when he lived,
but the best accounts I could

00:04:29.807 --> 00:04:34.273
see is near the beginning of
the seventh century B.C.E.

00:04:34.273 --> 00:04:37.970
And Cyrus the Great is
from Achaemenis' family,

00:04:37.970 --> 00:04:42.596
and so since they came to
power, this first really Persian

00:04:42.596 --> 00:04:44.801
empire, when the people talk
about the Persian empire

00:04:44.801 --> 00:04:47.494
they don't tend to refer to
the Median empire, they're

00:04:47.494 --> 00:04:49.327
really referring to the Achaemenid empire,

00:04:49.327 --> 00:04:52.140
that's why it's called Achaemenid.

00:04:52.140 --> 00:04:55.135
Now, in future videos we'll
talk more about what happened

00:04:55.135 --> 00:04:58.703
in the Achaemenid empire, but
you can see the extent of it

00:04:58.703 --> 00:05:02.962
was pretty significant and it
lasts for a little over 200

00:05:02.962 --> 00:05:06.277
years until they're
conquered by foreigners.

00:05:06.277 --> 00:05:09.102
And the foreigners that
conquer them are the Greeks.

00:05:09.102 --> 00:05:12.870
Philip of Macedon's son,
Alexander the Great, is able to,

00:05:12.870 --> 00:05:16.269
on some level, unify Greece and Persia.

00:05:16.269 --> 00:05:18.741
And it's interesting because
a lot of what we learn about

00:05:18.741 --> 00:05:21.705
ancient Persia, it's
accounts from the Greeks,

00:05:21.705 --> 00:05:25.030
from folks like Herodotus,
but during the time

00:05:25.030 --> 00:05:29.521
of classical Greece, Greece
was really a bit of a sideshow,

00:05:29.521 --> 00:05:32.573
it was really this kind of
thorn in the side of Persia.

00:05:32.573 --> 00:05:35.516
Persia was really where the power was.

00:05:35.516 --> 00:05:39.683
But as we get to the mid or
the end of the fourth century

00:05:41.292 --> 00:05:45.647
B.C.E., Persia weakens,
Greece unifies under Philip

00:05:45.647 --> 00:05:48.832
of Macedon and Alexander the
Great and Alexander the Great

00:05:48.832 --> 00:05:51.608
is able to conquer the Persian empire.

00:05:51.608 --> 00:05:54.020
And he is short-lived, we have
videos on Alexander the Great

00:05:54.020 --> 00:05:57.181
I encourage you to watch
them, his life is short-lived

00:05:57.181 --> 00:05:59.754
and his unified empire is
short-lived, but he has this

00:05:59.754 --> 00:06:03.546
dream of mixing the cultures
and really being a unified

00:06:03.546 --> 00:06:06.367
people, but as soon as he
dies his empire splits,

00:06:06.367 --> 00:06:09.882
but the Persian empire for the most part,

00:06:09.882 --> 00:06:12.751
is in the control of the Seleucid's.

00:06:12.751 --> 00:06:16.229
And the Seleucid dynasty, this
is essentially foreign rule

00:06:16.229 --> 00:06:19.947
'cause Seleucus, who
establishes Seleucid dynasty,

00:06:19.947 --> 00:06:22.852
he is one of Alexander's
generals, he's fundamentally

00:06:22.852 --> 00:06:26.397
Greek, and so the rulers of
the Seleucid dynasty are Greek.

00:06:26.397 --> 00:06:29.458
And you don't get back
to having Persian rule

00:06:29.458 --> 00:06:32.751
until 238 B.C.E.

00:06:32.751 --> 00:06:36.918
It's in 238 B.C.E. that the
Parthian's emerge to conquer

00:06:38.604 --> 00:06:40.855
the empire and so, once
again you could say,

00:06:40.855 --> 00:06:44.173
"Well, this is back to non-foreign rule."

00:06:44.173 --> 00:06:46.597
It's really important
to keep in mind, because

00:06:46.597 --> 00:06:50.815
in it's day the Achaemenid
empire was, if not the dominant,

00:06:50.815 --> 00:06:54.418
one of the very dominant
empires of the world.

00:06:54.418 --> 00:06:58.190
At it's peak it had a
population, this is roughly

00:06:58.190 --> 00:07:01.537
under Darius the Great, and
we'll talk more about him,

00:07:01.537 --> 00:07:03.876
he was an interesting
character, but the Achaemenid

00:07:03.876 --> 00:07:08.043
empire at it's peak had
approximately 50 million people.

00:07:09.114 --> 00:07:12.023
And that's a lot of people
at any time in history,

00:07:12.023 --> 00:07:13.457
but especially at that time in history

00:07:13.457 --> 00:07:15.213
because at that time in
history there was only

00:07:15.213 --> 00:07:17.870
a little over 100 million
people in the world,

00:07:17.870 --> 00:07:19.626
or at least that's our current estimates.

00:07:19.626 --> 00:07:22.408
So this is actually the largest
proportion of the world's

00:07:22.408 --> 00:07:27.322
population that any empire
has ever had in history,

00:07:27.322 --> 00:07:29.745
as far as we can tell, so
that gives it some claim

00:07:29.745 --> 00:07:32.910
to being maybe the greatest
or one of the greatest

00:07:32.910 --> 00:07:35.223
empires in world history.

00:07:35.223 --> 00:07:37.800
And then, as we get into
the Seleucid and especially

00:07:37.800 --> 00:07:40.502
the Parthian empire, you
know, in the West we talk

00:07:40.502 --> 00:07:42.924
a lot about the glory of the Roman empire,

00:07:42.924 --> 00:07:47.038
but the Parthian's were right
there beside of them, and

00:07:47.038 --> 00:07:51.240
they kind of went back and forth
but they were side by side,

00:07:51.240 --> 00:07:54.810
the peak of the Parthian
empire coincides with the peak

00:07:54.810 --> 00:07:57.251
of the Roman empire, and they
give each other space and

00:07:57.251 --> 00:08:00.650
they went back and forth
especially around the Middle East.

00:08:00.650 --> 00:08:03.630
And you have this empire
from the Parthian's you go to

00:08:03.630 --> 00:08:07.797
the Sassanian's and eventually
in the seventh century C.E.,

00:08:09.890 --> 00:08:12.398
Islam comes into the Persian empire

00:08:12.398 --> 00:08:14.281
and becomes the dominant religion.

00:08:14.281 --> 00:08:15.875
And so that might make you ask,

00:08:15.875 --> 00:08:18.738
"Well, what was the dominant
religion before that?"

00:08:18.738 --> 00:08:22.600
And the answer there is Zoroastrianism.

00:08:22.600 --> 00:08:25.683
Zoroastrianism.

00:08:29.318 --> 00:08:32.705
And it was really Cyrus
the Great, by establishing

00:08:32.705 --> 00:08:36.720
the Persian empire, who
really spreads Zoroastrianism.

00:08:36.720 --> 00:08:40.893
And Zoroastrianism is based
on their prophet Zarathustra.

00:08:40.893 --> 00:08:44.042
And when Zarathustra lived is
up for some debate, it might

00:08:44.042 --> 00:08:47.719
be as early as 1500 B.C.E.,
some people say it might

00:08:47.719 --> 00:08:51.932
be even right before even
coincident with the life

00:08:51.932 --> 00:08:53.979
of Cyrus the Great, so
there's some debate on when

00:08:53.979 --> 00:08:58.146
Zarathustra lived, but it
was a monotheistic religion,

00:08:59.127 --> 00:09:02.210
following the one god of Ahura Mazda.

00:09:07.625 --> 00:09:09.443
Ahura Mazda.

00:09:09.443 --> 00:09:12.755
And it was based on these
ideas of good thoughts lead

00:09:12.755 --> 00:09:15.416
to good words and good deeds.

00:09:15.416 --> 00:09:18.776
Other big ideas of the
Persian empire is their system

00:09:18.776 --> 00:09:20.947
of governments, of governants.

00:09:20.947 --> 00:09:25.047
Because it was such a
vast empire they delegated

00:09:25.047 --> 00:09:27.881
the emperor, the Shah and
Shah, the King of Kings,

00:09:27.881 --> 00:09:31.286
delegated authority to the
regions so each region,

00:09:31.286 --> 00:09:35.203
each satrapy had it's
governor called a satrap.

00:09:37.872 --> 00:09:40.124
And as we see over time, some
of these satraps got more

00:09:40.124 --> 00:09:43.973
power then maybe was intended
and then eventually took over.

00:09:43.973 --> 00:09:47.654
But this was a major empire
in the history of the world,

00:09:47.654 --> 00:09:51.821
they unified people, they're
famous for royal road

00:09:52.720 --> 00:09:57.619
that connected Sardis all the
way, all the way to Sousa,

00:09:57.619 --> 00:10:00.643
as you can imagine it would
have facilitated the transfer

00:10:00.643 --> 00:10:02.979
of knowledge and the transfer of trade.

00:10:02.979 --> 00:10:05.396
Under the Seleucid's you
had huge Greek influence,

00:10:05.396 --> 00:10:06.789
but it was two way street.

00:10:06.789 --> 00:10:09.331
Not only did the Greeks
influence the Persians,

00:10:09.331 --> 00:10:13.148
but the Persians heavily
influenced the Greeks.

00:10:13.148 --> 00:10:15.149
So with that, in the next
few videos we'll go into

00:10:15.149 --> 00:10:18.557
even more depth on the Persian empire

00:10:18.557 --> 00:10:21.390
and specifically the Achaemenid's.


Overview of ancient Greece

WEBVTT
Kind: captions
Language: en

00:00:00.205 --> 00:00:02.073
- [Salman] I am now
going to give an overview

00:00:02.073 --> 00:00:03.157
of ancient Greece.

00:00:03.157 --> 00:00:05.678
In future videos we're gonna
go into a lot more depth

00:00:05.678 --> 00:00:07.339
on a lot of these events and ideas.

00:00:07.339 --> 00:00:10.191
But this one is to give you
context on the big picture.

00:00:10.191 --> 00:00:14.358
And just to start, let's
begin with the name Greece.

00:00:15.295 --> 00:00:17.785
It turns out that the Greeks do not call

00:00:17.785 --> 00:00:21.361
where they live, Greece,
neither did the ancient Greeks.

00:00:21.361 --> 00:00:23.194
They called it Hellas.

00:00:24.101 --> 00:00:25.351
Hellas, Hellas.

00:00:27.019 --> 00:00:30.186
And the word Hellas comes from Hellen,

00:00:31.497 --> 00:00:33.449
so this comes from Hellen,

00:00:33.449 --> 00:00:35.891
which is this legendary
figure who is viewed

00:00:35.891 --> 00:00:38.924
as a progenitor of the Greek people.

00:00:38.924 --> 00:00:39.831
You could kind of view him

00:00:39.831 --> 00:00:41.743
as the father of the Greek people.

00:00:41.743 --> 00:00:45.166
And it's not well established
in the historical record

00:00:45.166 --> 00:00:48.364
when Hellen actually existed,

00:00:48.364 --> 00:00:51.886
but this is where we get
the name Hellas from.

00:00:51.886 --> 00:00:52.764
And it's very important.

00:00:52.764 --> 00:00:56.781
Do not confuse this Hellen, who was a man,

00:00:56.781 --> 00:00:59.146
with Helen of Troy.

00:00:59.146 --> 00:01:00.973
Helen of Troy was a different person.

00:01:00.973 --> 00:01:04.146
When I was a child and I
heard about Hellenic things

00:01:04.146 --> 00:01:06.946
or the Hellenic period, or the Hellenes,

00:01:06.946 --> 00:01:07.779
I was like, oh,

00:01:07.779 --> 00:01:10.385
maybe that's something
to do with Helen of Troy.

00:01:10.385 --> 00:01:11.218
No.

00:01:11.218 --> 00:01:15.070
That's referring to the
Greek progenitor Hellen.

00:01:15.070 --> 00:01:18.427
And so that's where the
word Hellas comes from,

00:01:18.427 --> 00:01:22.436
and ideas like Hellenes,
which is the Greek people.

00:01:22.436 --> 00:01:25.547
Or Hellenic, which is referring
to something that is Greek,

00:01:25.547 --> 00:01:27.116
or the Hellenistic Period,

00:01:27.116 --> 00:01:29.499
which we'll talk about
many videos from now,

00:01:29.499 --> 00:01:31.264
which is this period of Greek influence.

00:01:31.264 --> 00:01:35.053
Not just over Greece and
the Anatolian Peninsula,

00:01:35.053 --> 00:01:37.636
but over Persia and over Egypt.

00:01:38.585 --> 00:01:39.998
So with that out of the way,

00:01:39.998 --> 00:01:44.010
let's now talk about
the big arc of history

00:01:44.010 --> 00:01:45.706
of ancient Greece.

00:01:45.706 --> 00:01:49.074
And it's believed that the Greek Peninsula

00:01:49.074 --> 00:01:52.366
has been settled by human beings

00:01:52.366 --> 00:01:54.474
for thousands and thousands of years.

00:01:54.474 --> 00:01:56.047
And as time goes on we'll
hopefully understand

00:01:56.047 --> 00:01:57.761
more and more about them.

00:01:57.761 --> 00:01:59.372
But my timeline right over here

00:01:59.372 --> 00:02:01.460
starts with Mycenaean Greece,

00:02:01.460 --> 00:02:04.862
or it starts with the
end of Mycenaean Greece.

00:02:04.862 --> 00:02:06.275
In other videos we might talk more

00:02:06.275 --> 00:02:09.023
about the Mycenaean Empire.

00:02:09.023 --> 00:02:10.851
And as that empire falls,

00:02:10.851 --> 00:02:13.274
we enter into the Greek Dark Ages.

00:02:13.274 --> 00:02:15.122
And the reason why it's
called the Dark Ages,

00:02:15.122 --> 00:02:18.114
is there's not a lot of
historical record of this period

00:02:18.114 --> 00:02:21.031
roughly between 1100BCE and 800BCE.

00:02:22.326 --> 00:02:24.402
Now there's one event,

00:02:24.402 --> 00:02:26.944
and I'll kind of say that
with a slight emphasis

00:02:26.944 --> 00:02:29.810
or a question that is worth noting here.

00:02:29.810 --> 00:02:33.727
I have Trojan War question
mark around 1200BCE.

00:02:35.339 --> 00:02:38.555
Once again, there's not
a strong historic record

00:02:38.555 --> 00:02:42.697
for the Trojan War,
but it is a famous war,

00:02:42.697 --> 00:02:45.394
that was chronicled by Homer.

00:02:45.394 --> 00:02:47.484
And even Homer, we don't
know if he really existed,

00:02:47.484 --> 00:02:49.972
or whether he was an
entire literary tradition.

00:02:49.972 --> 00:02:51.622
But it was chronicled in the Iliad

00:02:51.622 --> 00:02:53.682
in the aftermath in the Odyssey.

00:02:53.682 --> 00:02:54.515
And once again,

00:02:54.515 --> 00:02:56.806
this was chronicled many
hundreds of years later,

00:02:56.806 --> 00:03:00.306
and even Homer is a semi-legendary figure.

00:03:01.284 --> 00:03:03.321
But when people talk about the Trojan Wars

00:03:03.321 --> 00:03:04.695
or you see movies about it,

00:03:04.695 --> 00:03:06.202
we're talking about something that,

00:03:06.202 --> 00:03:08.361
if it happened the way it happened,

00:03:08.361 --> 00:03:10.778
it's on the order of 1200BCE.

00:03:13.597 --> 00:03:16.215
Now as we exit the Greek Dark Ages,

00:03:16.215 --> 00:03:19.384
that's when we start to have
some of the institutions

00:03:19.384 --> 00:03:22.886
that really, that we now
identify with the ancient Greeks,

00:03:22.886 --> 00:03:24.286
get established.

00:03:24.286 --> 00:03:26.616
You have the Oracle at Delphi.

00:03:26.616 --> 00:03:29.972
The Oracle of Delphi, or Pythia,

00:03:29.972 --> 00:03:31.743
often known as the Oracle of Delphi.

00:03:31.743 --> 00:03:34.441
This is where leaders
of the Greek city-states

00:03:34.441 --> 00:03:38.886
went for direction to understand
what was likely to happen,

00:03:38.886 --> 00:03:40.356
to get prophecies.

00:03:40.356 --> 00:03:43.213
And this institution,
the Oracle at Delphi,

00:03:43.213 --> 00:03:47.469
lasts through this entire
period I have on my timeline,

00:03:47.469 --> 00:03:50.552
into Roman rule, for over 1000 years,

00:03:53.094 --> 00:03:56.828
where the Oracle at Delphi is
a very, very prominent figure

00:03:56.828 --> 00:03:59.905
in influencing Greek leaders.

00:03:59.905 --> 00:04:03.550
At around the same time, you
also have the Olympic Games,

00:04:03.550 --> 00:04:05.479
where they're held at Olympia,

00:04:05.479 --> 00:04:09.685
where people compete to
show their athletic prowess.

00:04:09.685 --> 00:04:12.187
And this ancient Olympic Games once again,

00:04:12.187 --> 00:04:15.187
it continues on for over 1000 years.

00:04:16.224 --> 00:04:20.103
Our modern Olympics are just
kind of a flash in the pan,

00:04:20.103 --> 00:04:24.338
and it was obviously modeled
after the ancient Olympics,

00:04:24.338 --> 00:04:27.541
compared to how long this lasted.

00:04:27.541 --> 00:04:30.624
Now when most people think of Greece,

00:04:31.495 --> 00:04:35.049
they're actually talking
about classical Greece.

00:04:35.049 --> 00:04:37.514
So this is the Classical
Period right over here.

00:04:37.514 --> 00:04:39.821
And we're gonna do videos
on a lot of these events,

00:04:39.821 --> 00:04:44.239
but it's roughly the period
between the Persian invasions

00:04:44.239 --> 00:04:46.614
that were successfully put off,

00:04:46.614 --> 00:04:50.903
and the rise of Alexander
and the fall of Alexander.

00:04:50.903 --> 00:04:54.001
And that's where you
have all of these ideas

00:04:54.001 --> 00:04:58.168
of Greek democracy really
kind of coming to the surface.

00:05:01.542 --> 00:05:04.197
Pericles, the Strategos of Athens,

00:05:04.197 --> 00:05:07.847
who had the influence to
really help democracy flourish.

00:05:07.847 --> 00:05:10.778
Under his leadership, or
during his leadership,

00:05:10.778 --> 00:05:13.395
you have the Acropolis and the Parthenon,

00:05:13.395 --> 00:05:17.958
these famous icons of Greek
culture being established.

00:05:17.958 --> 00:05:21.075
But once again, this is in this period.

00:05:21.075 --> 00:05:23.095
That's in this period right over here.

00:05:23.095 --> 00:05:25.190
This is also the period that we associate

00:05:25.190 --> 00:05:27.085
with the famous Greek philosophers.

00:05:27.085 --> 00:05:28.159
These lines right over here

00:05:28.159 --> 00:05:31.094
are the lives of Socrates and Plato,

00:05:31.094 --> 00:05:33.616
who is Socrates' student,

00:05:33.616 --> 00:05:35.158
established the famous academy.

00:05:35.158 --> 00:05:37.275
Aristotle who was Plato's student

00:05:37.275 --> 00:05:40.608
and famous tutor of Alexander the Great.

00:05:41.558 --> 00:05:44.122
Now as I mentioned, you
had these city-states,

00:05:44.122 --> 00:05:46.473
and the ones that are worth mentioning,

00:05:46.473 --> 00:05:48.296
all of them are worth mentioning.

00:05:48.296 --> 00:05:49.939
But I have in this diagram,

00:05:49.939 --> 00:05:52.252
the most significant
city-states of ancient Greece

00:05:52.252 --> 00:05:53.356
that you'll hear a lot about.

00:05:53.356 --> 00:05:55.051
We talked about the Oracle at Delphi,

00:05:55.051 --> 00:05:56.868
the Olympic Games at Olympia.

00:05:56.868 --> 00:05:59.471
A lot of the conversation
tends to focus around Sparta

00:05:59.471 --> 00:06:00.971
and around Athens.

00:06:03.739 --> 00:06:06.818
And then you'll also hear a
lot about Corinth and Thebes.

00:06:06.818 --> 00:06:10.651
Sparta is famous for its
militaristic society.

00:06:12.011 --> 00:06:13.001
It's often glorified.

00:06:13.001 --> 00:06:15.129
But it's also worth noting that they were

00:06:15.129 --> 00:06:16.516
significant slave owners.

00:06:16.516 --> 00:06:19.268
At different parts in Spartan history,

00:06:19.268 --> 00:06:22.659
they had somewhere between
seven and 20 slaves

00:06:22.659 --> 00:06:24.884
for every Spartan.

00:06:24.884 --> 00:06:27.614
Athens is famous for its philosophy.

00:06:27.614 --> 00:06:31.824
It's famous for the
birthplace of democracy.

00:06:31.824 --> 00:06:34.001
It's famous for its art, it's
famous for its architecture,

00:06:34.001 --> 00:06:36.481
all of these areas are
famous for its architecture.

00:06:36.481 --> 00:06:40.112
But it's also worth noting
that during the Golden Age,

00:06:40.112 --> 00:06:42.127
and you have the Athenian Empire,

00:06:42.127 --> 00:06:45.097
they were also pretty brutal
in putting down rebellion

00:06:45.097 --> 00:06:48.074
and in some ways subjugating
different people.

00:06:48.074 --> 00:06:50.935
So it depends how you want to view things.

00:06:50.935 --> 00:06:52.480
And we're gonna have a lot of videos

00:06:52.480 --> 00:06:54.660
on all of these things.

00:06:54.660 --> 00:06:57.032
But at that time, we talk
about these city-states,

00:06:57.032 --> 00:06:59.452
even though they shared a common language

00:06:59.452 --> 00:07:00.319
and common culture,

00:07:00.319 --> 00:07:02.945
they sent folks to the Olympic games,

00:07:02.945 --> 00:07:05.891
they went to the Oracle of Delphi,

00:07:05.891 --> 00:07:08.296
they were independent states.

00:07:08.296 --> 00:07:11.591
And it wasn't until you
have Philip of Macedonia

00:07:11.591 --> 00:07:15.302
in the fourth century right over here,

00:07:15.302 --> 00:07:19.061
where he starts to really
unify these Greek city-states,

00:07:19.061 --> 00:07:22.144
and it culminates with his
son, Alexander the Great.

00:07:22.144 --> 00:07:25.288
And Alexander the Great
not only unifies Greece,

00:07:25.288 --> 00:07:27.690
but he takes over the Persian Empire,

00:07:27.690 --> 00:07:30.057
and really kind of with his death,

00:07:30.057 --> 00:07:31.492
and he has a very short life,

00:07:31.492 --> 00:07:33.696
he ushers in the Hellenistic period,

00:07:33.696 --> 00:07:36.258
where you have Greek culture influencing

00:07:36.258 --> 00:07:37.718
that entire region.

00:07:37.718 --> 00:07:41.740
Not only Greece, not only
what was the Persian Empire,

00:07:41.740 --> 00:07:43.313
the Middle East, Egypt,

00:07:43.313 --> 00:07:47.802
that whole region gets
influenced by Greek culture.

00:07:47.802 --> 00:07:50.958
And Greece, I guess you
could say, at the end,

00:07:50.958 --> 00:07:53.230
finally gets under Roman control,

00:07:53.230 --> 00:07:55.484
and it depends which
date you wanna use it.

00:07:55.484 --> 00:07:58.415
In the middle of the second century BCE

00:07:58.415 --> 00:08:01.273
is when Greece itself falls to Rome,

00:08:01.273 --> 00:08:04.242
but then other parts of,
I guess you could say,

00:08:04.242 --> 00:08:07.907
the Hellenistic world,
finally succumb to Rome.

00:08:07.907 --> 00:08:12.189
For example, Ptolemaic Egypt
in the first century BCE.

00:08:12.189 --> 00:08:13.290
But even then,

00:08:13.290 --> 00:08:15.692
even when it becomes
part of the Roman Empire,

00:08:15.692 --> 00:08:19.859
it influences the Roman Empire
very, very, very heavily.

00:08:20.874 --> 00:08:23.415
Now other things that you
will hear us talk about

00:08:23.415 --> 00:08:24.664
when we discuss the Greeks,

00:08:24.664 --> 00:08:28.130
besides the democracy and the philosophy,

00:08:28.130 --> 00:08:30.353
we're gonna talk a lot about wars.

00:08:30.353 --> 00:08:35.323
And it's worth noting what
Greek warriors looked like.

00:08:35.323 --> 00:08:37.715
So this is a depiction of Hoplites,

00:08:37.715 --> 00:08:41.752
which are Greek citizen
soldiers in ancient Greece.

00:08:41.752 --> 00:08:44.211
And you'll also here about a phalanx.

00:08:44.211 --> 00:08:46.197
A phalanx is a formation where they walked

00:08:46.197 --> 00:08:48.753
or they marched very tightly together.

00:08:48.753 --> 00:08:51.423
And when archers came they
would put all their shields up,

00:08:51.423 --> 00:08:53.933
and they'd almost be
like this armored tank.

00:08:53.933 --> 00:08:58.227
And it was a very effective
method of warfare.

00:08:58.227 --> 00:09:00.178
Another word that you will hear associated

00:09:00.178 --> 00:09:02.637
with Sparta and those slaves is Helots.

00:09:02.637 --> 00:09:04.341
Those were the names of those slaves.

00:09:04.341 --> 00:09:06.162
They weren't owned by individuals,

00:09:06.162 --> 00:09:09.155
they were actually owned by the state.

00:09:09.155 --> 00:09:11.020
Now some of the other cities here,

00:09:11.020 --> 00:09:13.031
Corinth, will come up a lot.

00:09:13.031 --> 00:09:15.058
It has a very strategic location

00:09:15.058 --> 00:09:16.601
in the Isthmus of Corinth.

00:09:16.601 --> 00:09:18.767
Notice to get from the mainland,

00:09:18.767 --> 00:09:22.733
or I guess into the
Peloponnesian Peninsula,

00:09:22.733 --> 00:09:25.170
you have to go through this Isthmus.

00:09:25.170 --> 00:09:29.083
Thebes right here was a
significant rival to Athens

00:09:29.083 --> 00:09:31.585
at different periods of Greek history.

00:09:31.585 --> 00:09:34.459
It was the dominant city.

00:09:34.459 --> 00:09:35.442
Now the last thing I wanna mention

00:09:35.442 --> 00:09:38.757
is there is a ton of culture
that comes from the Greeks,

00:09:38.757 --> 00:09:41.654
and a lot of words that we even use today.

00:09:41.654 --> 00:09:43.182
For example, the word draconian,

00:09:43.182 --> 00:09:46.202
which is used for something
that's very harsh.

00:09:46.202 --> 00:09:48.052
Well that comes from Draco's law,

00:09:48.052 --> 00:09:52.796
which came in the seventh
century BCE from Athens.

00:09:52.796 --> 00:09:55.213
He was an Athenian legislator

00:09:56.134 --> 00:09:59.013
who composed a very harsh series of laws.

00:09:59.013 --> 00:10:01.139
That's where the word
draconian comes from.

00:10:01.139 --> 00:10:02.751
When people say something is spartan,

00:10:02.751 --> 00:10:05.683
they kind of imagine it's
something that's very basic

00:10:05.683 --> 00:10:07.920
or you just have the necessities.

00:10:07.920 --> 00:10:11.193
And it comes from the
idea of Spartan culture

00:10:11.193 --> 00:10:13.317
that they really,

00:10:13.317 --> 00:10:16.684
everything revolved
around military necessity.

00:10:16.684 --> 00:10:18.611
Even the word laconic,

00:10:18.611 --> 00:10:22.066
which means someone who says just enough

00:10:22.066 --> 00:10:23.646
to get their meaning across.

00:10:23.646 --> 00:10:27.653
It comes from the region
where Sparta is, Laconia.

00:10:27.653 --> 00:10:29.574
The Spartans were famous for their kind of

00:10:29.574 --> 00:10:31.074
very terse speech.

00:10:31.954 --> 00:10:33.679
Famously, when Philip of Macedon

00:10:33.679 --> 00:10:34.848
was threatening the Spartans,

00:10:34.848 --> 00:10:37.410
and he's saying, "If you
don't come on to my side

00:10:37.410 --> 00:10:39.122
"I'm going to do this and that to you

00:10:39.122 --> 00:10:42.512
"if you don't become part
of my kingdom, my empire,

00:10:42.512 --> 00:10:43.686
"I'm going to do this to your city,

00:10:43.686 --> 00:10:45.649
"I'm going to do that to your people."

00:10:45.649 --> 00:10:49.780
And the Spartan's famous reply was, "If."

00:10:49.780 --> 00:10:53.180
which is kind of a good
example of laconic speech.

00:10:53.180 --> 00:10:57.166
With that one word they
were able to convey a lot.

00:10:57.166 --> 00:10:58.981
So I'm going to leave you there.

00:10:58.981 --> 00:11:00.465
In the next few videos,

00:11:00.465 --> 00:11:02.642
we're going to go into some depth on this.

00:11:02.642 --> 00:11:04.112
But it's important to realize

00:11:04.112 --> 00:11:05.564
that when people talk
about ancient Greece,

00:11:05.564 --> 00:11:07.682
they're talking about a
large span of history,

00:11:07.682 --> 00:11:09.924
and most of what we associate
with ancient Greece,

00:11:09.924 --> 00:11:14.065
the Acropolis, the
Parthenon, the Persian Wars,

00:11:14.065 --> 00:11:16.246
the great Greek philosophers,

00:11:16.246 --> 00:11:19.759
most of that is associated
with the classical period,

00:11:19.759 --> 00:11:21.684
often associated with the Golden Age.

00:11:21.684 --> 00:11:24.017
Which is right around there.

00:11:26.004 --> 00:11:27.566
Well before this period,

00:11:27.566 --> 00:11:29.845
the Greeks weren't all these philosophers

00:11:29.845 --> 00:11:31.192
sitting around in togas.

00:11:31.192 --> 00:11:32.388
They might've been wearing togas,

00:11:32.388 --> 00:11:34.071
but at these earlier periods

00:11:34.071 --> 00:11:37.023
they were more adventurers and conquerors,

00:11:37.023 --> 00:11:39.002
and they might have
been in small villages.

00:11:39.002 --> 00:11:42.224
And eventually those
evolved into the city-states

00:11:42.224 --> 00:11:44.373
that especially in Athens and Sparta

00:11:44.373 --> 00:11:47.880
had their Golden Age in
this period right over here.


Meaning of Lagrange multiplier

WEBVTT
Kind: captions
Language: en

00:00:00.498 --> 00:00:01.331
- [Instructor] Hey folks.

00:00:01.331 --> 00:00:03.189
In this video I wanna show you
something pretty interesting

00:00:03.189 --> 00:00:06.367
about these Lagrange multipliers
that we've been studying.

00:00:06.367 --> 00:00:08.555
So the first portion I'm just
gonna kind of get this set up,

00:00:08.555 --> 00:00:11.172
which is a lot of review
from what we've seen already,

00:00:11.172 --> 00:00:12.958
but I think you're really
gonna like where this is going

00:00:12.958 --> 00:00:14.222
in the end.

00:00:14.222 --> 00:00:16.111
So one of the examples I
showed, and I think this is a

00:00:16.111 --> 00:00:17.750
pretty nice prototypical example

00:00:17.750 --> 00:00:20.002
for constrained optimization problems,

00:00:20.002 --> 00:00:21.213
is that you're running a company

00:00:21.213 --> 00:00:23.772
and you have some kind of revenue function

00:00:23.772 --> 00:00:26.232
that's dependent on various choices

00:00:26.232 --> 00:00:27.301
you make in running the company,

00:00:27.301 --> 00:00:29.804
and I think I said the
number of hours of labor

00:00:29.804 --> 00:00:32.310
you employ and the number
of tons of steel you use,

00:00:32.310 --> 00:00:34.970
you know, if you were
manufacturing something metallic.

00:00:34.970 --> 00:00:37.678
And, you know, this might be
modeled as some multivariable

00:00:37.678 --> 00:00:39.513
function of h and s, right
now we don't really care

00:00:39.513 --> 00:00:40.879
about the specifics.

00:00:40.879 --> 00:00:42.591
And you're trying to maximize this, right,

00:00:42.591 --> 00:00:44.579
that's kind of the
whole point of this unit

00:00:44.579 --> 00:00:47.063
that we've been doing, is
that you're trying to maximize

00:00:47.063 --> 00:00:49.005
some function, but you have a constraint.

00:00:49.005 --> 00:00:51.716
This is the real world, you
can't just spend infinite money,

00:00:51.716 --> 00:00:54.488
you have some kind of budget,
some sort of amount of money

00:00:54.488 --> 00:00:57.472
you spend as a function of
those same choices you make,

00:00:57.472 --> 00:01:00.421
the hours of labor you employ,
the tons of steel you use.

00:01:00.421 --> 00:01:02.228
And this, again, it's gonna equal some

00:01:02.228 --> 00:01:04.259
multivariable function
that tells you, you know,

00:01:04.259 --> 00:01:06.064
how much money you spend
for a given amount of hours

00:01:06.064 --> 00:01:08.761
and given number of tons of steel.

00:01:08.761 --> 00:01:10.715
And you set this equal to some constant,

00:01:10.715 --> 00:01:14.431
this tells you the amount of
money you're willing to spend.

00:01:14.431 --> 00:01:16.857
And our goal has been to
maximize some function,

00:01:16.857 --> 00:01:18.712
subject to a constraint like this.

00:01:18.712 --> 00:01:20.413
And the mental model you have in mind

00:01:20.413 --> 00:01:22.485
is that you're looking in the input space,

00:01:22.485 --> 00:01:23.890
inside the x-y plane,

00:01:23.890 --> 00:01:25.889
or I guess really, it's the
h-s plane in this case, right.

00:01:25.889 --> 00:01:29.408
Your inputs are h and s,
and points in this plane

00:01:29.408 --> 00:01:31.317
tell you possible choices you can make

00:01:31.317 --> 00:01:33.670
for hours of labor and tons of steel.

00:01:33.670 --> 00:01:35.595
And you think of this budget

00:01:35.595 --> 00:01:38.702
as some kind of curve
in that plane, right.

00:01:38.702 --> 00:01:41.421
All the sets of h and s that equal $10,000

00:01:41.421 --> 00:01:43.577
is gonna give you some kind of curve.

00:01:43.577 --> 00:01:45.135
And the core value we care about is that,

00:01:45.135 --> 00:01:46.774
when you maximize this revenue,

00:01:46.774 --> 00:01:48.407
you know, when you set
it equal to a constant

00:01:48.407 --> 00:01:51.607
I'm gonna call M star, that's
like the maximum possible

00:01:51.607 --> 00:01:54.168
revenue, that's gonna give you a contour

00:01:54.168 --> 00:01:56.275
that's just barely tangent

00:01:56.275 --> 00:01:58.988
to the constraint curve.

00:01:58.988 --> 00:02:00.014
And if that seems unfamiliar,

00:02:00.014 --> 00:02:03.328
definitely take a look at the
videos preceding this one.

00:02:03.328 --> 00:02:04.787
But, just to kind of continue the review,

00:02:04.787 --> 00:02:06.122
this gave us the really nice property

00:02:06.122 --> 00:02:08.744
that you look at the gradient vector

00:02:08.744 --> 00:02:11.167
for the thing you're
trying to maximize, R,

00:02:11.167 --> 00:02:14.793
and that's gonna be proportional
to the gradient vector

00:02:14.793 --> 00:02:19.659
for the constraint function,
for this B, so gradient of B.

00:02:19.659 --> 00:02:21.543
And this is because
gradients are perpendicular

00:02:21.543 --> 00:02:22.474
to contour lines.

00:02:22.474 --> 00:02:25.176
Again, this should feel mostly
like review at this point.

00:02:25.176 --> 00:02:29.990
So the core idea was that
we take this gradient of R,

00:02:29.990 --> 00:02:31.929
and then make it proportional,
with some kind of

00:02:31.929 --> 00:02:34.599
proportionality constant lambda,

00:02:34.599 --> 00:02:37.178
to the gradient of B, to the gradient

00:02:37.178 --> 00:02:38.947
of the constraint function.

00:02:38.947 --> 00:02:41.893
And up till this point, this value lambda

00:02:41.893 --> 00:02:43.562
has been wholly uninteresting.

00:02:43.562 --> 00:02:45.403
It's just been a
proportionality constant, right,

00:02:45.403 --> 00:02:47.612
because we couldn't guarantee
that the gradient of R

00:02:47.612 --> 00:02:49.411
is equal to the gradient of B.

00:02:49.411 --> 00:02:50.617
All we care about is that they're pointing

00:02:50.617 --> 00:02:51.893
in the same direction.

00:02:51.893 --> 00:02:53.959
So we just had this constant sitting here,

00:02:53.959 --> 00:02:57.533
and all we really said is
make sure it's not zero.

00:02:57.533 --> 00:02:59.677
But here, we're gonna get
to where this little guy

00:02:59.677 --> 00:03:01.677
actually matters.

00:03:01.677 --> 00:03:03.359
So, if you'll remember, in the last video,

00:03:03.359 --> 00:03:06.672
I introduced this function
called the Lagrangian,

00:03:06.672 --> 00:03:07.736
the Lagrangian.

00:03:07.736 --> 00:03:09.018
And it takes in multiple inputs,

00:03:09.018 --> 00:03:11.234
they'll be the same inputs that you have

00:03:11.234 --> 00:03:13.605
for your budget function
and your revenue function,

00:03:13.605 --> 00:03:15.033
or more generally, the constraint

00:03:15.033 --> 00:03:16.731
and the thing you're trying to maximize.

00:03:16.731 --> 00:03:18.961
It takes in those same variables,

00:03:18.961 --> 00:03:21.850
but, also, as another one of its inputs,

00:03:21.850 --> 00:03:23.596
it takes in lambda.

00:03:23.596 --> 00:03:25.915
So, it is a higher-dimensional function

00:03:25.915 --> 00:03:28.854
than both of these two, because
we've got this extra lambda.

00:03:28.854 --> 00:03:32.184
And the way it's defined looks
a little strange at first,

00:03:32.184 --> 00:03:34.690
it just seems kind of like this random

00:03:34.690 --> 00:03:37.339
hodgepodge of functions
that we're putting together.

00:03:37.339 --> 00:03:38.770
But, last time, I kind of walked through

00:03:38.770 --> 00:03:39.747
why this makes sense.

00:03:39.747 --> 00:03:41.732
You take the thing you're
trying to maximize,

00:03:41.732 --> 00:03:44.305
and you subtract off this lambda,

00:03:44.305 --> 00:03:48.176
multiplied by the constraint function,

00:03:48.176 --> 00:03:50.426
which is B of those inputs,

00:03:51.802 --> 00:03:55.043
minus, and then whatever
this constant is here, right.

00:03:55.043 --> 00:03:56.956
I'm gonna give it a name,
I'm gonna call this constant

00:03:56.956 --> 00:03:58.132
lowercase b.

00:03:58.132 --> 00:04:00.352
So maybe we're thinking of it as $10,000,

00:04:00.352 --> 00:04:03.097
but it's whatever your actual budget is.

00:04:03.097 --> 00:04:04.356
So we think of that, and I'm just gonna

00:04:04.356 --> 00:04:08.857
emphasize here that
that's a constant, right,

00:04:08.857 --> 00:04:12.153
that this b is being treated
as a constant right now.

00:04:12.153 --> 00:04:13.874
You know, we're thinking
of h and s and lambda

00:04:13.874 --> 00:04:16.564
all as these variables, and this gives us

00:04:16.564 --> 00:04:19.510
some multivariable function.

00:04:19.510 --> 00:04:22.494
And if you'll remember
from the last video,

00:04:22.494 --> 00:04:24.323
the reason for defining this function

00:04:24.323 --> 00:04:26.875
is it gives us a really
nice compact way to solve

00:04:26.875 --> 00:04:29.401
the constraint optimization problem.

00:04:29.401 --> 00:04:32.507
You set the gradient of L equal to zero,

00:04:32.507 --> 00:04:34.444
or really the zero vector,
right, it'll be a vector

00:04:34.444 --> 00:04:36.655
with three components here.

00:04:36.655 --> 00:04:39.637
And when you do that, you'll
find some solution, right,

00:04:39.637 --> 00:04:44.324
you'll find some solution,
which I'll call h star,

00:04:44.324 --> 00:04:48.334
s star, and lambda, here
I'll give it that green

00:04:48.334 --> 00:04:50.501
lambda color, lambda star.

00:04:55.116 --> 00:04:57.367
You'll find some value
that, when you input this

00:04:57.367 --> 00:05:00.832
into the function, the
gradient will equal zero.

00:05:00.832 --> 00:05:02.450
And, of course, you might
find multiple of these, right,

00:05:02.450 --> 00:05:05.059
you might find multiple
solutions to this problem,

00:05:05.059 --> 00:05:08.352
but what you do is, for each
one of them you're gonna take

00:05:08.352 --> 00:05:11.568
a look at h star and s star,
then you're gonna plug those

00:05:11.568 --> 00:05:13.786
into the revenue function, or
the thing that you're trying

00:05:13.786 --> 00:05:14.795
to maximize.

00:05:14.795 --> 00:05:17.199
And, typically, you only get
a handful, you get a number,

00:05:17.199 --> 00:05:18.768
then you can actually
plug each one of them into

00:05:18.768 --> 00:05:21.196
the revenue function, and
you'll just check which one

00:05:21.196 --> 00:05:22.908
of them makes this function the highest.

00:05:22.908 --> 00:05:25.436
And whatever the highest value
this function can achieve,

00:05:25.436 --> 00:05:29.333
that is M star, that is the
maximum possible revenue,

00:05:29.333 --> 00:05:31.250
subject to this budget.

00:05:32.371 --> 00:05:34.785
But it's interesting that when
you solve this, you get some

00:05:34.785 --> 00:05:37.918
specific value of lambda,
right, there's a specific

00:05:37.918 --> 00:05:41.529
lambda star that will be
associated with the solution.

00:05:41.529 --> 00:05:43.659
And, like I said, this
turns out not to just be

00:05:43.659 --> 00:05:45.336
some dummy variable.

00:05:45.336 --> 00:05:48.605
It's gonna carry information
about how much we can increase

00:05:48.605 --> 00:05:51.876
the revenue if we increase that budget.

00:05:51.876 --> 00:05:53.518
And, here, let me show you what I mean.

00:05:53.518 --> 00:05:57.876
So we've got this M star,
and I'll just write it again,

00:05:57.876 --> 00:05:59.306
M star here.

00:05:59.306 --> 00:06:01.716
And what that equals, I'm
saying that's the maximum

00:06:01.716 --> 00:06:03.000
possible revenue.

00:06:03.000 --> 00:06:05.834
So that's gonna be the revenue
when you evaluate it at

00:06:05.834 --> 00:06:07.353
h star,

00:06:07.353 --> 00:06:08.853
h star and s star.

00:06:10.692 --> 00:06:13.365
And h star and s star, they
are whatever the solution

00:06:13.365 --> 00:06:18.018
to this gradient of the Lagrangian
equals zero equation is.

00:06:18.018 --> 00:06:20.092
You set this multivariable
function equal to the

00:06:20.092 --> 00:06:23.377
zero vector, you solve when
each of its partial derivatives

00:06:23.377 --> 00:06:26.202
equal zero, and you'll
get some kind of solution.

00:06:26.202 --> 00:06:28.103
So when you plug that
solution in the revenue,

00:06:28.103 --> 00:06:31.081
that gives you the
maximum possible revenue.

00:06:31.081 --> 00:06:33.981
But what we could do is
consider this as a function

00:06:33.981 --> 00:06:35.967
of the budget.

00:06:35.967 --> 00:06:38.542
Now, this is the kind of thing
that looks a little bit wacky

00:06:38.542 --> 00:06:40.831
if you're just looking at the formulas.

00:06:40.831 --> 00:06:42.619
But if you actually
think about what it means

00:06:42.619 --> 00:06:44.880
in this context of kind
of a revenue and a budget,

00:06:44.880 --> 00:06:46.741
I think it's actually pretty sensible,

00:06:46.741 --> 00:06:50.212
where, really, if we consider
this b no longer to be

00:06:50.212 --> 00:06:52.464
constant but something that
you could change, right,

00:06:52.464 --> 00:06:55.169
you're wondering, well what
if I had a $20,000 budget,

00:06:55.169 --> 00:06:57.283
or what if I had a $15,000 budget?

00:06:57.283 --> 00:06:59.608
You wanna ask the question,
what happens as you change

00:06:59.608 --> 00:07:00.850
this b.

00:07:00.850 --> 00:07:04.677
Well, the maximizing
value, h star and s star,

00:07:04.677 --> 00:07:08.596
each one of those guys is
gonna depend on b, right.

00:07:08.596 --> 00:07:11.422
As you change what this
constant is, it's gonna change

00:07:11.422 --> 00:07:13.950
the values at which the
gradient of the Lagrangian

00:07:13.950 --> 00:07:15.633
equals zero.

00:07:15.633 --> 00:07:18.800
So, I'm gonna rewrite this function as

00:07:20.308 --> 00:07:23.226
the revenue evaluated
at h star and s star,

00:07:23.226 --> 00:07:25.352
but now I'm gonna consider
that h star and s star

00:07:25.352 --> 00:07:27.852
each as functions of b, right,

00:07:28.875 --> 00:07:30.259
because they depend on it in some way.

00:07:30.259 --> 00:07:33.065
As you change b, it changes
the solution to this problem

00:07:33.065 --> 00:07:35.238
It's very implicit and it's
kind of hard to think about.

00:07:35.238 --> 00:07:37.460
It's hard to think, okay,
as I change this b, how much

00:07:37.460 --> 00:07:38.628
does that change h star.

00:07:38.628 --> 00:07:40.304
Well that depends on what the, you know,

00:07:40.304 --> 00:07:42.963
what the definition of R
was and everything there.

00:07:42.963 --> 00:07:45.155
But, in principle, in this
context, I think it's quite

00:07:45.155 --> 00:07:45.988
intuitive.

00:07:45.988 --> 00:07:48.040
You have a maximum possible revenue,

00:07:48.040 --> 00:07:51.030
and that depends on what your budget is.

00:07:51.030 --> 00:07:55.075
So, what turns out to be a
beautiful, absolutely beautiful

00:07:55.075 --> 00:07:56.075
magical fact

00:07:57.204 --> 00:07:59.204
is that this lambda star

00:08:00.389 --> 00:08:03.472
is equal to the derivative of M star,

00:08:04.903 --> 00:08:08.820
the derivative of this
maximum possible revenue

00:08:09.862 --> 00:08:13.695
with respect to b, with
respect to the budget.

00:08:14.796 --> 00:08:17.002
And let me just show you what
that actually means, right.

00:08:17.002 --> 00:08:19.064
So if, for example, let's say you did

00:08:19.064 --> 00:08:22.288
all of your calculations and
it turned out that lambda star

00:08:22.288 --> 00:08:23.705
was equal to 2.3.

00:08:25.112 --> 00:08:27.167
You know, previously that just
seemed like some dummy number

00:08:27.167 --> 00:08:29.214
that you ignore, and you
just look at whatever the

00:08:29.214 --> 00:08:30.935
associated values here are.

00:08:30.935 --> 00:08:33.041
But if you plug this in the
computer and you see lambda star

00:08:33.041 --> 00:08:37.665
equals 2.3, what that means is,
for a tiny change in budget,

00:08:37.665 --> 00:08:40.765
like let's say your budget
increases from 10,000

00:08:40.765 --> 00:08:43.515
to 10,001, it goes up to $10,001,

00:08:45.855 --> 00:08:48.848
you increase your budget by
just a little bit, a little db.

00:08:48.848 --> 00:08:51.896
Then the ratio of the change
in the maximizing revenue

00:08:51.896 --> 00:08:53.896
to that db is about 2.3.

00:08:54.826 --> 00:08:57.204
So what that would mean
is, increasing your budget

00:08:57.204 --> 00:09:00.330
by a dollar is gonna increase M star,

00:09:00.330 --> 00:09:03.573
over here it would mean
that M star increases

00:09:03.573 --> 00:09:05.656
by about, you know, $2.30

00:09:07.065 --> 00:09:09.261
for every dollar that
you increase your budget.

00:09:09.261 --> 00:09:10.940
And that's information
you'd wanna know, right?

00:09:10.940 --> 00:09:12.840
If you see that this
lambda star is a number

00:09:12.840 --> 00:09:15.279
bigger than one, you'd say,
hey, maybe we should increase

00:09:15.279 --> 00:09:16.134
our budget.

00:09:16.134 --> 00:09:18.948
We increase it from $10,000
to 10,001 and we're making

00:09:18.948 --> 00:09:20.016
more money.

00:09:20.016 --> 00:09:22.866
So, maybe, as long as lambda
star is greater than one,

00:09:22.866 --> 00:09:24.798
you should keep doing
whatever it takes to increase

00:09:24.798 --> 00:09:26.273
that budget.

00:09:26.273 --> 00:09:28.927
So this fact is quite surprising, I think,

00:09:28.927 --> 00:09:31.488
and it seems like it totally
comes out of nowhere.

00:09:31.488 --> 00:09:34.225
So what I'm gonna do in the
next video is prove this to you,

00:09:34.225 --> 00:09:37.640
is prove why this is true,
why this lambda star value

00:09:37.640 --> 00:09:41.879
happens to be the rate of
change for the maximum value

00:09:41.879 --> 00:09:43.595
of the thing we're trying to maximize

00:09:43.595 --> 00:09:46.709
with respect to this constant,
with respect to whatever

00:09:46.709 --> 00:09:49.538
constant you set your
constraint function equal to.

00:09:49.538 --> 00:09:51.554
For right now, though, I
just want you to kind of

00:09:51.554 --> 00:09:54.461
try to sit back and digest
what this means in the context

00:09:54.461 --> 00:09:56.665
of this specific economic example.

00:09:56.665 --> 00:09:58.644
And, even if you never
looked into the proof

00:09:58.644 --> 00:09:59.697
and never understood it there,

00:09:59.697 --> 00:10:02.181
I think this is an
interesting and even useful

00:10:02.181 --> 00:10:05.841
tidbit of knowledge to have
about Lagrange multipliers.

00:10:05.841 --> 00:10:07.174
So with that, I'll see
you in the next video.


Diadochi and the Hellenistic Period

WEBVTT
Kind: captions
Language: en

00:00:00.000 --> 00:00:02.063
- [Instructor] Where we
left off in the last video,

00:00:02.063 --> 00:00:06.230
Alexander dies in 323 BCE,
at the young age of 32.

00:00:07.736 --> 00:00:09.986
And even though he conquered
all of this territory,

00:00:09.986 --> 00:00:12.404
it was a very short-lived empire.

00:00:12.404 --> 00:00:15.753
And what happens next is a period known

00:00:15.753 --> 00:00:19.222
as the Wars of the Diadochi, and let me

00:00:19.222 --> 00:00:22.502
write down this word, Diadochi.

00:00:22.502 --> 00:00:25.502
Diadochi translates into successors,

00:00:27.252 --> 00:00:29.251
and these are the various leaders,

00:00:29.251 --> 00:00:31.907
and mainly generals, of Alexander

00:00:31.907 --> 00:00:35.407
who then fought for control of the empire.

00:00:36.620 --> 00:00:39.502
It's a very bloody
period, a lot of different

00:00:39.502 --> 00:00:41.472
Diadochi going after each other,

00:00:41.472 --> 00:00:43.785
or after each other's families,

00:00:43.785 --> 00:00:46.588
and what eventually happens
over the next few decades

00:00:46.588 --> 00:00:49.485
is Alexander's empire, the empire that he

00:00:49.485 --> 00:00:53.652
establishes, gets split up
into a few major empires.

00:00:56.219 --> 00:00:58.068
What you see on this
map here, you see most

00:00:58.068 --> 00:01:01.985
of Persia, and the Anatolian
Peninsula right over here,

00:01:01.985 --> 00:01:06.667
really the bulk of the old
Achaemenid Persian Empire.

00:01:06.667 --> 00:01:09.368
It gets under control of Seleucus,

00:01:09.368 --> 00:01:11.857
and he establishes the Seleucid dynasty,

00:01:11.857 --> 00:01:13.924
the Seleucid Empire.

00:01:13.924 --> 00:01:15.407
Let me write this down right here.

00:01:15.407 --> 00:01:18.824
This is Seleucid, so the Seleucid Empire.

00:01:21.106 --> 00:01:24.523
Egypt right over here,
this gets taken control

00:01:24.523 --> 00:01:27.940
of another general of Alexander, Ptolemy,

00:01:29.291 --> 00:01:32.756
and he establishes the Ptolemaic Empire

00:01:32.756 --> 00:01:34.907
and the Ptolemaic dynasty.

00:01:34.907 --> 00:01:35.740
Ptolemaic.

00:01:37.939 --> 00:01:40.805
And then Macedon ends up under control

00:01:40.805 --> 00:01:42.739
once again of another Diadochi,

00:01:42.739 --> 00:01:44.272
remember the Diadochi are the successors,

00:01:44.272 --> 00:01:47.024
all of these characters right over here.

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These are three of the various Diadochi,

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three of the more successful
Diadochi right over here.

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But what the Macedonian components

00:01:56.738 --> 00:01:59.655
of Alexander's Empire, for the most part,

00:01:59.655 --> 00:02:03.422
end up under the control
of Antigonus's dynasty,

00:02:03.422 --> 00:02:07.221
which ends up being called
the Antigonid dynasty.

00:02:07.221 --> 00:02:08.054
Antigonid.

00:02:10.454 --> 00:02:13.413
And this, and as you can see, it's not all

00:02:13.413 --> 00:02:15.204
of the empire Alexander established.

00:02:15.204 --> 00:02:17.903
What we have in red here,
these are independent

00:02:17.903 --> 00:02:20.297
states that did not get subsumed

00:02:20.297 --> 00:02:24.464
into the Seleucid, the Ptolemaic,
or the Antigonid Empires,

00:02:26.275 --> 00:02:28.709
You can imagine, over the
next several hundred years,

00:02:28.709 --> 00:02:30.774
they're going back and forth, there's an

00:02:30.774 --> 00:02:34.041
ebb and flow of control
of these various empires,

00:02:34.041 --> 00:02:36.040
but these are the three most significant,

00:02:36.040 --> 00:02:39.908
especially the Ptolemaic and the Seleucid.

00:02:39.908 --> 00:02:42.190
What this establishes is what a lot

00:02:42.190 --> 00:02:44.907
of historians refer to as a new period

00:02:44.907 --> 00:02:47.673
of especially this part of the world.

00:02:47.673 --> 00:02:51.406
When we go from shortly
before the Persian invasions

00:02:51.406 --> 00:02:53.723
of Greece all the way
to Alexander the Great,

00:02:53.723 --> 00:02:55.928
we refer to that as Classical Greece,

00:02:55.928 --> 00:02:59.428
but now we're going from Classical Greece,

00:03:02.862 --> 00:03:04.712
with the death of
Alexander in the beginning

00:03:04.712 --> 00:03:07.711
of the Wars of the Diadochi for control,

00:03:07.711 --> 00:03:09.935
this sets up a new period, often referred

00:03:09.935 --> 00:03:13.185
to by historians as Hellenistic Period.

00:03:20.886 --> 00:03:23.170
And the Hellenistic Period is referring

00:03:23.170 --> 00:03:26.337
to the fact that all of this territory

00:03:27.502 --> 00:03:29.703
that was conquered by Alexander the Great,

00:03:29.703 --> 00:03:32.319
and later gets split after
the Wars of the Diadochi

00:03:32.319 --> 00:03:36.087
between these Diadochi
establishing these various empires,

00:03:36.087 --> 00:03:38.753
they had huge influence of Greek culture.

00:03:38.753 --> 00:03:42.986
You had ruling dynasties
that were essentially Greek,

00:03:42.986 --> 00:03:44.786
whether you're in Ptolemaic Egypt,

00:03:44.786 --> 00:03:48.436
Seleucid Persia, or Antigonid Macedonia.

00:03:48.436 --> 00:03:49.636
Obviously the Macedonians were already

00:03:49.636 --> 00:03:51.969
a very strong Greek culture.

00:03:53.765 --> 00:03:57.931
And it's a time where you have the spread

00:03:57.931 --> 00:04:00.981
of the culture, you have
a bit of fulfillment

00:04:00.981 --> 00:04:05.148
of Alexander the Great's
goal of creating this very,

00:04:05.998 --> 00:04:09.181
this mashup, so to speak,
of the various cultures

00:04:09.181 --> 00:04:12.207
of the region, the Greco, and the Persian,

00:04:12.207 --> 00:04:14.581
and the Egyptian cultures.

00:04:14.581 --> 00:04:17.430
Now the Hellenistic Period starts to end

00:04:17.430 --> 00:04:21.430
as each of these various
empires get overthrown.

00:04:22.464 --> 00:04:27.046
The Seleucid Empire, in
the third century BCE,

00:04:27.046 --> 00:04:30.778
it gets more and more overtaken
by the Parthian Empire.

00:04:30.778 --> 00:04:33.861
Parthia starts as a satrap, a region,

00:04:35.453 --> 00:04:37.142
of the Seleucid Empire, but it eventually

00:04:37.142 --> 00:04:39.375
takes control over much of Persia.

00:04:39.375 --> 00:04:41.358
So this is the Parthanian, sorry,

00:04:41.358 --> 00:04:44.441
the Parthian Empire, right over here.

00:04:50.025 --> 00:04:52.842
And the last vestiges
of the Seleucid Empire

00:04:52.842 --> 00:04:55.725
are eventually defeated
by the Roman legions,

00:04:55.725 --> 00:04:57.624
and you'll see this is a common trend here

00:04:57.624 --> 00:05:00.007
because, at the time of Alexander,

00:05:00.007 --> 00:05:03.460
on the Italian peninsula, you start having

00:05:03.460 --> 00:05:06.308
a city-state that's becoming
more and more powerful,

00:05:06.308 --> 00:05:08.191
and more and more of an empire.

00:05:08.191 --> 00:05:10.758
And as we will see, it starts to subsume

00:05:10.758 --> 00:05:14.207
a lot of the regions we talked about.

00:05:14.207 --> 00:05:17.124
Ptolemaic Egypt, it gets overthrown

00:05:18.310 --> 00:05:20.810
by the Roman Empire in 30 BCE,

00:05:21.706 --> 00:05:24.957
and the Antigonid dynasty gets overthrown

00:05:24.957 --> 00:05:26.973
by the Roman Empire,
they're actually the first

00:05:26.973 --> 00:05:31.056
to get overthrown by the
Roman Empire, in 168 BC.

00:05:32.273 --> 00:05:34.606
So this period, this Hellenistic Period,

00:05:34.606 --> 00:05:37.039
the takeaway, it's a
period, I'm talking about

00:05:37.039 --> 00:05:40.006
hundreds of years in a matter
of five or six minutes,

00:05:40.006 --> 00:05:42.589
but this is a period
where you had significant

00:05:42.589 --> 00:05:45.821
Greek influence over a very large period,

00:05:45.821 --> 00:05:49.356
or a very large area of
land, and it eventually ends

00:05:49.356 --> 00:05:51.455
with a lot of the western portions

00:05:51.455 --> 00:05:54.855
falling under Roman control,
and the eastern portions,

00:05:54.855 --> 00:05:58.860
especially Persia, falling
under Parthian control.