I would like to learn about the history of Japan, it must be fascinating.
Yes it is actually. The archipelago was inhabited by humans back in prehistoric times.
Wow, that long?  And when does civilization began there?
Hm, I'm not really sure. Somewhere between the 4th and 9th century Japans' many kingdoms and tribes came together under one government.
Is that when they first got and emperor?
I believe so. The imperial dynasty continues in Japan.