Galactic Empire (Asimov)

In Isaac Asimov's Robot/Empire/Foundation series of novels, the Galactic Empire is an empire consisting of planets settled by humans across the whole galaxy. It is clearly based on the Roman Empire.

The Galactic Empire consists of 25 million inhabited worlds, all colonized by Settlers from Earth (as opposed to Spacers), although by the time when the novels are set, no one remembers that humans originated from that small planet. It is not certain when it was founded - the dates in Empire and Foundation series are given in GE (Galactic Era, and later FE, Foundation Era), not AD, and the evidence on when the Galactic Era started varies from book to book, but the one that fits most of them is about 12,000 AD, and it lasts for about 12,000 years after its foundation.

The Empire's capital is Trantor, a planet covered entirely by a giant city, located near the center of the Galaxy. It is both the center of power in the Galaxy, and also the administrative head. Most of the Galaxy's population (three quarters of it), was in the central third of the Galaxy.

In 12,010 GE Cleon I becomes Emperor upon the death of his father, Stanel VI. Ten years later, Cleon I would find his place in history as it was over the next (last) 18 years of his reign that Hari Seldon began to formulate his science of psychohistory.

In 12,068 GE, a mathematician called Hari Seldon, by the means of psychohistory, the science he invented, predicts the fall of the Empire. He predicts that the empire will collapse within 300 years, leading to a 30,000 year period of anarchy before a Second Empire is established. To influence events so that the interregnum period will be only 1,000 years and not 30,000, he creates a small haven of technology in a corner of the galaxy (on the planet Terminus) called the Foundation, whose job it will be to preserve knowledge from the collapse, thus reducing the time required for the next Empire to rebuild.

Two-hundred years later, when the Empire was well into its collapse, it launches an attack against the Foundation, led by general Bel Riose. By this time, the Foundation holds economic control over a large portion of the galactic periphery, and word of the Foundation is starting to reach the Empire at the Galactic Core. Riose repeatedly defeats the Foundation through brilliant tactical and strategic planning. Before he can complete his conquest, however, he is recalled by the Emperor, tried for treason, and executed, as the Emperor fears that the general might become strong enough to dethrone him.

Following the defeat of Bel Riose and the subsequent death of Cleon II, the Galactic Empire falls into a civil war. After this civil war an even more rapid phase of decline begins, with weak emperors losing vast amounts of territory and strong ones barely holding onto what they have. Three-hundred years after the Foundation's creation, the Galactic Empire's capital world, the city-planet Trantor, is sacked.

The Empire now bases itself on "Neo-Trantor", which is almost mockingly named so; it was an agricultural colony that used to feed Trantor. The Galactic Empire, which used to touch every planet in the Milky Way galaxy, is reduced to 20 agricultural planets. It is dwarfed by most barbarian kingdoms.

The greatest conqueror the Galaxy has ever seen, The Mule, defeater of the First Foundation, later conquers the pathetic remains of the Galactic Empire as well.

George Lucas used elements from Asimov's books to construct the universe in which Star Wars is set, including the Galactic Empire, although his Empire was founded for evil purposes. Additionally, Coruscant, the imperial capital planet covered completely with buildings, is a direct borrowing of Asimov's Trantor.