The Milky Way Galaxy occurs fictional in Isaac Asimov’s Robot, Empire and Foundation novels – later expanded by Gregory Benford, Greg Bear and David Brin – depict a future history spanning roughly 25,000 years.
Overview[]
In this canon, humanity spreads from 21st‑century Earth to thousands of planets, eventually forming a First Galactic Empire, which Hari Seldon’s psychohistorical analysis predicts will collapse. Seldon founds the First Foundation on Terminus to preserve knowledge and guide the galaxy toward a Second Empire.
The books describe successive political orders, colonial regions and epochs: a Spacer era of robot‑assisted colonies (21st–30th c. AD), the long First Galactic Empire (established “1 GE” ~11,586 AD,
its fall, and the rise of the Foundation and Second Foundation. Authorized sequels by Benford/Bear/Brin interweave with Asimov’s originals.
Political Structure[]
Spacer Worlds[]
The original exosolar colonies (e.g. Aurora, Solaria, Melpomenia) settled in the 21st–30th c. by Earth, enabled by robots. Each Spacer world was self-governing, often under technocratic councils or rigid social orders. Spacer society was high‑tech and long-lived: Spacers “fully rely on positronic robots… and have much longer lifespans than Earthmen”. By the 5th millennium AD their culture stagnated. The Spacers are culturally united only by their advanced robotics and by the Three Laws of Robotics; they hold themselves above “short-lived” Earth‑Settlers.
Settler Worlds[]
After 4724 AD, Earth was allowed to colonize new worlds. These Settler planets (collectively the “Outer Worlds”) were populous but had minimal robot labor. They governed themselves locally (many as oligarchies or democracies) and were hostile to robots. Over time they outnumber the Spacer worlds: one account notes that eventually the “Settler worlds spread across the galaxy, outnumbering the Spacer worlds”. Many Settler worlds later come under Foundation influence or fall into desuetude.
Earth's decay[]
(Sol) itself becomes a backwater penal world by the Empire’s height (radioactive and taboo after 4922 AD. Some unique societies appear (e.g. the all‑female Solarians, the planet Gaia with a group consciousness), but these are exceptions.
First Galactic Empire (Cleon Dynasty)[]
A hereditary monarchy centered on Trantor. At its height it ruled millions of worlds divided into sectors/prefectures. The Emperor (e.g. Cleon I, II, …) on Trantor was served by a vast bureaucracy (in late Imperial times the Commission of Public Safety wielded executive power). According to Asimov’s chronology, the Trantorian kingdom founded ~5500 AD became the Trantorian Empire by ~11,086 AD, and “in year 11,586 (1 GE)” it formally became the Galactic Empire with Trantor as capital. The Empire endured ~12,000 years before its collapse (the last Emperor dies ~350 FE).
First Foundation[]
Founded in “50 F.E.” (Foundation Era) on the remote world Terminus. Ostensibly an encyclopedia project, it was secretly tasked by Seldon with preserving science and eventually rebuilding a new Empire. Terminus’s government begins as a Board of Encyclopedists, then transitions to a series of elected or appointed Mayors (Salvor Hardin, Hober Mallow, etc.) and, by the end of the series, a Foundation Federation. Over its history the Foundation grows from a scientific colony to a political-military power.
Second Foundation[]
A secret cadre of “mentalics” (psychologists and telepaths) founded by Seldon on Trantor. Its purpose is to clandestinely safeguard the Seldon Plan by influencing key individuals’ minds. Second Foundationers (the First Speaker, etc.) maintain a hidden rule from Trantor even as the First Foundation develops publicly. Asimov’s novels reveal the Second Foundation only late in the saga, and its location on Trantor (“the seat of the former Galactic Empire”) is kept secret until the very end.
Galactic Geography[]
The galaxy is commonly divided into core and rim regions: Trantor sits in the Core, Terminus on the Outer Rim (the “end of the line”).
Major worlds and divisions include:
- Sol / Earth: Humanity’s birthplace, originally “Alpha Centauri” is often used for the solar system. By the Foundation era Earth is radioactive and abandoned
- Aurora (Spacer Homeworld): The first extrasolar colony (Tau Ceti system, ~70 ly from Sol) founded in 2065 AD. Called the “World of the Dawn,” Aurora leads the Spacer states. (Aurora orbits around the Core region.) Other Spacer worlds include Solaria, Compassion, etc., each largely self-contained.
- Trantor (Imperial Capital): An ecumenopolis (city‑covered planet) at or near the galactic center. By Seldon’s time it hosts over a trillion inhabitants in vast urban sectors. Trantor is subdivided into hundreds of administrative sectors (e.g. Dahl, Ery, Streeling, Wye, Mycogen, etc.). It houses the Imperial Palace, Galactic Library and other centers of power.
- Terminus (First Foundation): A small, resource-poor oceanic world at the far rim. It has virtually no strategic value except housing the Foundation. Terminus’s isolation (few nearby stars) and name (“end of the line”) reflect its peripheral location. The Foundation’s capital is Terminus City, home to the Seldon Vault and Encyclopedia.
- Galaxy’s Outer vs. Inner Regions: Many stories refer to “Outer Regions” (including Terminus) and “Central Regions” (around Trantor). The Empire’s prefectures span both. Notable non-Imperial worlds include Anacreon, Kalgan, and the 50 Spacer planets (all scattered throughout the galaxy).
Technology and Society[]
Human society in the Foundation universe is heavily shaped by technology and genetics. Key developments include
Robotics[]
Early expansion is driven by positronic robots obeying Asimov’s Three Laws. On Spacer worlds, robots perform nearly all labor, enabling the aristocratic, long-lived Spacer lifestyle. (The novels later introduce a “Zeroth Law” that Daneel Olivaw and Giskard develop to prioritize humanity’s welfare.) By the First Empire era, true robots have vanished except for the immortal R. Daneel Olivaw, but their legacy influences politics (e.g. Earth’s ban on robots and eventual exodus)
Faster-than-light Travel[]
Hyperspace jump drives (called “hyperatomics”) are the norm by the 21st century. Interstellar voyages happen routinely (e.g. Earth reaches Aurora in 2065). In the Second Foundation Trilogy Benford introduced artificial wormhole portals for rapid travel, though Bear’s follow-up largely reverts to the classical hyperspace system to maintain continuity.
Nuclear and Fusion Power[]
Energy weapons and fusion drives underlie much of the technology. By Foundation times, planets can generate vast power (the Encyclopedia Foundation converts to a “power religion” based on nuclear technology). The Foundation’s first crises all involve atomic “power” as a strategic resource (reflected in the Seldon Vault recordings).
Psychohistory[]
Seldon’s creation is a mathematical “demographic” science that predicts the statistical fate of large populations. It is the dominant science behind the Foundation’s actions. Seldon’s immutable plan governs galactic history, even though individuals are free.
Second-Foundation Psychotechnics[]
The Second Foundation’s “mentalics” are experts in psychology, telepathy and mind control. They employ these powers secretly (e.g. pacifying the Mule, manipulating Foundation leaders) to nudge the Seldon Plan back on course.
Societal Traits[]
Life expectancy and culture differ widely. Spacers routinely live ~200–300 years, Settlers ~80–90. Spacer society is elitist and xenophobic toward short-lived “Earthers,” whereas Settlers value hard work, reproduction and practical governance. Under the Empire, humans live in densely urban worlds (Trantor’s entire surface) and adhere to rigid class structures. The Foundation’s society blends scientific rationalism (especially in early centuries) with merchant oligarchy as it grows.
Later Additions[]
The Benford/Bear/Brin novels introduce advanced future-tech that Asimov never explicitly described. For example, they posit a galaxy‑wide information “Mesh” on Trantor and large-scale AI simulations of historical figures (Joan of Arc, Voltaire) to study psychohistory. These novels also explore demographic technologies (wormholes vs. hyperspace) and cosmic forces that are not present in Asimov’s original canon.
Epochs and Transitions[]
Robotic Era and Spacer Colonization (21st–30th c. AD)[]
Susan Calvin and her colleagues develop robots on Earth. In 2065, Earth’s first interstellar voyage founds Aurora. Over the next millennia Spacers (modified humans) colonize dozens of worlds. In ~3720 AD they win the “Three-Week War” with Earth, forcing Earthmen to cede space travel for 1,000 years. In 4724 AD Earth is finally allowed to resume colonization, launching the long-lived Settler age. By 4922 AD, Earth has been deliberately rendered radioactive (by Spacer plotters) and becomes uninhabitable, leaving humanity dispersed.
Rise of the Empire (10th–12th millennium)[]
Over many millennia Earth’s colonies gradually coalesce into larger polities. By 11,086 AD a Trantorian Empire controls about half the galaxy. In 11,586 AD (1 GE) it formally becomes the First Galactic Empire, with Trantor as capital. Technology (FTL travel, stable fusion power) enables rapid travel and communication across the Empire. Society is relatively stable but decadent.
Foundation Era (12,000–13,000 AD)[]
In 12,067 G.E. Hari Seldon unveils psychohistory and the Fall prophecy. The Foundation on Terminus is secretly established in 1 GE (50 FE) under the guise of an Encyclopedia project. Seldon’s crises unfold on schedule, each crisis solved by the Foundation, enabling it to expand. Meanwhile the Mule (a mutant conqueror) briefly interrupts Seldon’s Plan (ca. 306 FE) before dying. By ~350 FE the First Empire has truly collapsed (the last Emperor dies) and the Foundation is effectively the dominant power in most of the galaxy’s habitable worlds. Psychohistory predicts roughly 1,000 FE of “dark ages” before a Second Empire arises, but thanks to the Plan this period will be limited to about a millennium instead of 30,000 years
Aftermath and Second Empire[]
By the end of Asimov’s original series (380–400 FE), the First Foundation rules a new empire in most of the galaxy (often called the Foundation or Federation) and the Second Foundation has assured the Plan’s success. Hari Seldon’s ultimate goal – a Second Galactic Empire – is foretold to form around 1000 FE., achieving lasting peace in the galaxy. The exact details of this Second Empire lie beyond the scope of the novels.
Second Foundation Trilogy Developments[]
The authorized sequels by Benford, Bear and Brin add context to the above chronology. Foundation’s Fear (1997) occurs during Seldon’s early career (between Forward the Foundation parts), Foundation and Chaos (1998) overlaps the start of Foundation, and Foundation’s Triumph (1999) follows the recording of Seldon’s holograms.These novels introduce new elements (e.g. a Trantorian data‐network “Mesh,” simulated avatars of historical figures, and wormhole travel) and tie together loose plot threads, but ultimately remain consistent with Asimov’s universe. They are officially published by Asimov’s estate and often grouped as a “Second Foundation Trilogy”.
Sources[]
Detailed information is drawn from Asimov’s novels and timeline summaries, particularly the Foundation series and Robots and Empire, as documented in the Foundation universe lore.