text: Galactic empires are in many cases consciously modeled on historical Earth-bound empires. Asimov stated explicitly that the Galactic Empire whose fall is depicted in his Foundation books is also modeled on the Roman Empire, with the author taking direct inspiration from the historical writings of Edward Gibbon, even to the point of basing some individual characters on historical figures. Specifically, Pebble in the Sky, which is set on Earth – a poor and backward province of the Galactic Empire – is modeled on Roman-ruled Judea in the 1st century AD. Asimov's Earth – like the historical Judea – is sharply polarized between those who accept the Imperial authority and the fanatic "Zealots" who hatch violent plots of bloody rebellion and are the book's clear villains.
  Foundation is depicted as having started life as a Foundation of scholars, taking up just one city on one faraway planet and setting up a modest municipal government headed, naturally, by a Mayor. Through a centuries-long series of developments which are the main subject matter of the Foundation Series, the Foundation gains enormous power and territory and comes to rule virtually as many stellar systems as the earlier fallen Empire - but continues to call itself "Foundation" rather than "Empire", and its ruler - though wielding as much power as any Emperor - retains the title of "Mayor".