-13.7Gy to -7000 AT: Preterragen Era

Preterragen era
Image from Steve Bowers

Scrollable Timeline

Orion's Arm Tranquility Calendar Conversion Tool


Big Bang + Several seconds - hypothetical Alpha civilisation.
Big Bang + 380,000 years - recombination era - the Universe becomes transparent.
Big Bang + 100 million years - formation of first stars.


Before the formation of the Solar System and of Earth.


Formation of the Solar System and Earth, outgassing of first atmosphere and oceans, bombardment by left-over planetesimals and debris, volcanism and formation of first continents, evolution of first microorganisms.


On Earth, most of the planetary surface was covered in a single global ocean, and the sky was shrouded by a haze layer that thrived in the carbon dioxide-rich reducing atmosphere. The planet's cooling interior permitted a primitive form of plate tectonics to begin. Life on the Archean Earth consisted of relatively simple bacteria and archaea; cyanobacteria represent some of the organisms that could be found during this time.

Interstellar Civilization HIE236PPE (disappeared 2-3 GYA).
Homeworld: Little is known except possible Planet Type.
Biology: Little information except possible Evoltype.
Known for: Titaniforming. Turning a world into Titanian type.
Impact on Earth's evolution: 0


The oxygen level in the atmosphere of Earth began rising at the beginning of this eon, triggering the Great Oxidation Event that caused a severe mass extinction and the Huronian glaciation, but also enabled the emergence of aerobic lifeforms afterward. Eukaryotic lifeforms first appeared during the earlier part of the eon, followed by the development of Earth's plate tectonics into the modern regime and the first fungi. Towards the end of the eon, animals and plants first evolved.

1.45 billion years ago: The Archivists released their enigmatic diamondoid information spheres. Apart from these objects, absolutely nothing is known of the nature or origin of this species.

1.1 billion years ago: The Jacks, a species of floaters occupying Jovian planets, appear for the first time, but their civilization is short-lived and cyclical. The species disappears after a few tens of thousands of years in space.

788 million years ago: The Jacks re-appear after having disappeared for unknown reasons; their new civilization collapses after 112,000 years.

780 million years ago: the Halogenics (Interstellar Civilization HIE282NPE) form a very large number of worlds to meet their peculiar biochemistry. Impact on Earth's evolution: 0 (no evidence territory extended to Sol System; Solsys lacked the correct abundance of elements).

560 million years ago: At least 158 worlds are ecoformed with a distinctive high-temperature Vitriolic ecotype biota by unknown xenosophonts who have been designated as the Thiogens.


On Old Earth atmospheric oxygen reaches present levels, ozone shield screens out ultraviolet radiation and allows complex life to live in the shallows, age of invertebrates, fish, amphibians, and finally reptiles, life emerges from the sea to colonise the land, pteridophyte and gymnospermous plants, mild to tropical conditions and warm shallow seas interspersed with Ordovician and Permo-Carboniferous ice ages, continents cluster into the supercontinent of Pangea.

500 million years ago: origin of Oceanus Ultimata .

451 million years ago: The Jacks rise from dormancy and form a new civilization, which collapses after 56,000 years.

400 million years ago: appearance of the alien Hygeras Object (152-3343 Gm-A).

The Hov's'sa and the Tkzeph vanished 312 million years ago. Impact on Earth's evolution: none (no evidence that territory extended to Sol System).


On Old Earth, the age of archosaurian reptiles, dinosaur megafauna, sea-reptiles, pterosaurs, ammonites. Mammals small and insignificant. Conditions warm and tropical worldwide. Supercontinent of Pangea breaks up into Laurasia and Gondwana. Modern corals, insects, fish and finally flowering plants evolve.

196 million years ago: species HIE636MZE (Makers) apparently was exterminated by a self-replicating swarm of its own creation. Four of the five different alien civilizations existing in the same galactic arm at the time of the swarm (three of which belong to the same species, HIE634MZE) attempted to design defenses against the swarm; one did not have the necessary skills and undertook a mass exodus ranging over 7,000 light years.

180 to 120 million years ago: the Muuh evolve to primitive sophonce, according to Muuh sources.

125 million years ago: planetary civilization HIE565MZE (Moundbuilders) disappears. Biology: Little information. Impact on Earth's evolution: 0 (no known interstellar travel).

120 million years ago: the Muuh develop interstellar spaceflight and start a long slow expansion, according to Muuh sources.

90 million years ago: The Jacks form their most recent civilization, which collapses after 82,000 years.


Age of mammals, birds, modern invertebrates, current continents emerge, initial tropical conditions give rise to colder drier climate, evolution of anthropoid apes and finally australopithecine hominids.

50 million years ago: the Muuh achieve spaceflight and interstellar travel according to some Muuh sources. This may either be the first instance or a revival of an earlier civilization.

40 million years ago: estimated establishment of BGC-based xenosophont virch world Steelcliff. BGC is BioGeoComputing.

33 million years ago: the Tunnlers (Interstellar civilization HIE441CZE) become extinct. This advanced civilisation left behind a number of usable wormholes. Impact on Earth's evolution: 0 (no evidence territory extended to Sol System).

28-32 million years ago: the Soft Ones are provolved by the Muuh to sapience.

31 million years ago: interstellar civilization HIE121CZE (The Lost) disappears.
Homeworld: Possibly destroyed/devastated. Biology: Information limited.
Impact on Earth's evolution: Uncertain.

28 million years ago: the "Soft Ones" slowly develop several technological cultures.

25 million years ago: Unnamed species HIE300CZE (The Bad Idea) provolved by the Muuh.

c. 16 million years ago: appearance of the Black Acropolis civilization.

14.8 million years ago: The Muuh are slaughtered by a fleet of automated war machines and only a few colonies are spared. At about the same time the "Black Acropolis" civilization abruptly disappears. The Lhagharians HIE072CZE withdraw from known space. Some explain these events on Dawn Hunters or other supposed inhibitor civilizations, but there is no confirmed evidence this is the case.

13 million years ago: terraforming swarm and artificial phylum the Cybyota appear in a long range seedship and colonise several planets before the swarm loses impetus.

10.7 million years ago: Labyrinth complex constructed by an unknown alien race. HIE106CZE according to Hamilton Institute.

8.3 million years ago: "Soft Ones" again contacted by a Muuh provolution ship. The oldest indigenous Soft One recorded history dates from this time.

7.2 million years ago the Iahi Daon colonial empire becomes extinct. Impact on Earth's evolution: 0 (no evidence that territory extended to Sol System).

5.4 million years ago: the long-lived silicon-gen civilization HIE072CZE (Lhagharians) is almost overrun by its own replicating swarms. Their own Enforcers saved them but were let loose on the rest of the galaxy as 'tracker mines' that are still a threat to unwary starships.

4.7 million years ago: Soft Ones achieve starfaring capability. They begin sub-relativistic colonizing of nearby star systems. Friendly contact with a number of other civilizations.

4 million years ago: the Doreens (interplanetary civilization HIE500CZE=HIE282RZE/D1) become extinct. Note: evolved from life forms left behind by "Halogenics" on the planet Afri II nearly 780 million years before, but culturally completely unrelated. Impact on Earth's evolution: 0 (no known successful interstellar travel).

3.6 million years ago: Auld Limner species raised to sophonce by a Soft Ones artisan clade. It is believed these "progenitors" may have also provolved of a number of local species in the Perseus or Outer Arm.

3.15 million years ago: Several "Soft One" and other sophont species leave this region of the galaxy in a great exodus.

2.8 million years ago: Thyresta, civilization arises on their homeworld, Tawattaran. Biology: endoskeletal communal-living carbon-based oxygen-breathers. Impact on Earth's evolution: none - destroyed themselves before attaining starfaring capability.


On Earth, the first emergence of Oldowan stone tool culture on (various hominid species, the Ice Ages, Rise of Man (Homo erectus, Neanderthal and Cro-Magnon) and use of stone tools and fire, Pleistocene megafauna worldwide, many interglacial warm periods, extinction of Megafauna.

Circa 1.5 million years ago: On Earth, Acheulian stone hand axe develops (Homo erectus/heidelbergensis/ergaster).

1.2 million years ago: the Ultimates colonize several Black Acropolis biospheres and after a short period of expansion settle into a static society.

Circa 950,000 years ago: To'ul'h civilisation is equivalent to Old Earth's Agricultural Age; this complex culture remains more or less stable for hundreds of thousands of years. Many empires are built and collapse over this time, but the corrosive environment prevents the development of most metal technology and the lack of an energy subsidy from forests or hydrocarbon deposits prevents the evolution of an Industrial Age.

Circa 400,000 years ago: On Earth, fire is used for warmth cooking and tool modification (Homo erectus).

350,000 years ago: the "Great Reformation", an attempt by the Ultimates of the Shining Path Morph to revive the morphospecies, institutes a brief renaissance, and a period of colonisation ("The Seeding") of nearby worlds.

300,000 years ago: Geminga Supernova explodes, forming the cloud known as the Local Bubble.

204,000 years ago: the last of the Ultimate Colonies ("Fruits") disappear. In the sheltered biospheres of the Black Acropolis the descendants of the Shining Path Morph have once long ossified into a self-cocooned equilibrium state.

circa 195,000 years ago: at about this time on Earth the first anatomically modern human beings (Homo sapiens sapiens) arise.

161,700 B.T.: The beginnings of the current Pas'utu'ril civilization's recorded history. It is believed that at least three, and perhaps as many as eight, Pas'utu'ril civilizations have arisen, flourished, and collapsed prior to the current one.
156,250 B.T.: The approximate beginning of the Pas'utu'ril Industrial Age among the more advanced clans.
155,893 B.T.: The first Pas'utu'ril is launched into orbit around Tsi'wadzj by the Akh'djir clan.
155,877 B.T.: The first inter-alliance war employing nuclear (fission) weapons is fought, marking the birth of the Atomic Age on Tsi'wadzj.
155,863 B.T.: The Pas'utu'ril civilization is devastated and some parts of the planet depopulated for decades by a global war involving the massive use of thermonuclear weapons.
155,355 B.T.: The first orbital spaceflight since the war is launched by the reconstituted Azkh'tsir clan.
155,284 B.T.: The global telecommunications network, controlled by several AIs, crashes when the AIs begin sabotaging each other's areas of responsibility in an internecine war for dominance.
154,673 B.T.: The first interstellar mission is launched from Tsi'wadzj by a consortium led by the Hlu'khat clan.
154,468 B.T.: The "signal" is emitted from the vicinity of Tsi'wadzj, presumably by accident.

102,000 BT (100,000 b.c.e): the cocooned Ultimates are slowly diminishing numbers.

52,000-38,000 BT (50,000-36,000 b.c.e): the most recent cycle of "Auld Limner" civilization begins.

Circa 72,000-34,000 BT (70,000-32,000 b.c.e.): Middle Paleolithic Mousterian stone tool technology (Homo sapiens neanderthalensis).

Circa 52,000 BT (50,000 b.c.e.): Sharp increase in diversity of human artifacts. Homo sapiens sapiens populations expand and absorb or displace other subspecies.

Circa 40,00 BT (38,000 b.c.e.): Upper Palaeolithic Aurignacian stone tool technology develops (Homo sapiens sapiens).

38,000-20100 BT (36,000-18,100 b.c.e.): Auld Limner Empire, a short-lived dominion some 2000 light years in diameter; Limners are a survivor or successor species in at least three star systems.

25883 BT (23864 b.c.e.): beginning of the To'ul'h Calendar.

Circa 24000 BT (22000 b.c.e.): neanderthal humans extinct in Europe.

Circa 12,000-10,000 BT (10000-8000 b.c.e.): Humans' animal husbandry and primitive agriculture develop in many forms.

Circa 10,000 BT (8000 b.c.e.): first permanent towns of humans.

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The Agricultural Age

  • Archivists  - Text by Richard Baker
    Vanished builders of certain hi-tech objects.
  • Auld Limner  - Text by Peter Kisner, M. Alan Kazlev and Anders Sandberg
    Perseus Arm (and possibly also Outer Arm) space-faring predecessors of the Limners.
  • Black Acropolis  - Text by Anders Sandberg
    A Dyson swarm built by a vanished civilization that has since been colonised by a number of other species.
  • Cybyota  - Text by Steve Bowers
    Mechanical/biological world-seeding and terraforming agents of non-Terragen origin that have apparently evolved into independent life forms since their origin.
  • Doreen/Doreens  - Text by Stephen Inniss, expanded and amended from original material by Anders Sandberg
    Chlorine world, former home of the extinct Doreens.
  • First Plague, The (To'ul'h Prime)  - Text by James Rogers
    Plague in ancient To'ul'hian historical times.
  • Galactic History  - Text by M. Alan Kazlev
    Branch of science and school of philosophy dealing with the history of mindkind in the Galaxy as a whole.
  • Geological Time, Geological Time Scale - Text by M. Alan Kazlev
    The history of a Terrestrial Class planet in terms of its formation and major stages of development. It is usually measured in many millions of years. The divisions used (from the largest (longest time) to the smallest (shortest time period) are: eon, era, period, epoch, and age.
  • Halogenics  - Text by Stephen Inniss
    The Halogenics are a hypothetical clade or group of clades, now believed to be extinct. They seeded a large number of chlorine worlds about 780 million years ago.
  • Hamilton Institute of Exopaleontology  - Text by Aaron Hamilton, M. Alan Kazlev, John M. Dollan
    One of the great scientific Houses of the Integration, the Institute was founded on the new University planet of Upali C/D II during the golden age of the 6th millennium, when relativistic exploration ships were increasingly encountering ancient and enigmatic ruins and relict tech of lost civilizations.
  • HIE-072-CZE (Lhagharians)  - Text by Aaron Hamilton
    Species which withdrew from the Orion Arm 5.4 million years ago.
  • HIE-121-CZE (The Lost)  - Text by Aaron Hamilton
    Xenosophonts which vanished 31 million years ago.
  • HIE-156-CZE (Jesters)  - Text by James Rogers
    Extinct alien species known only from ancient Muuh records.
  • HIE-233-MPE (Jacks)  - Text by Anders Sandberg; expanded by Stephen Inniss
    The Jacks (officially known as HIE-233-MPE) are a xenosophont species, or possibly a cluster of related species, named for a toy of ancient human baseline origin called a "Jack-in-a-box". Their name springs from the fact that they are apparently neither extinct nor extant; instead they have "popped up" several times in the past and may or may not return at some point in the future.
  • HIE-300-CZE (The Bad Idea)  - Text by Steve Bowers
    Predatory species provolved by the Muuh; hopefully extinct.
  • HIE-636-MZE (Makers)  - Text by Aaron Hamilton, updated by Steve Bowers
    The first indisputable physical relic of an alien civilisation capable of extraplanetary activity, discovered in orbit around Epsilon Scuptoris A in 1465 AT by a First Federation Exploration mission.
  • Hov's'sa  - Text by Aaron Hamilton
    Extinct aquatic xenosophonts.
  • Hovssian Epoch - Text by M. Alan Kazlev
    Local epoch in the Bentharis geological timescale, characterised by the presence of proto-Hov's'sean presophonts and then full Hov's'sa and Hov's'sa civilization. It is equivalent to the earlier late Carboniferous period, about 325 to 312 million years ago
  • Iahi Daon Empire  - Text by Aaron Hamilton, some comments by Steve Bowers
    Xenosophont species extinct for more than 7 million years; known only from remains on the former homeworld and from some massive generation ships.
  • Ice Age  - Text by Steve Bowers
    Any period of prolonged and widespread glaciation on a terrestrial world.
  • Kalpa - Text by M. Alan Kazlev
    A generalized Sophic term for a huge period or cycle of time; e.g. the life span of the cosmos. [Sanskrit - from the verbal root klrip to be in order]
  • Labyrinth  - Text by Todd Drashner
    Mars like world toward the outer Perseus Arm, known for its alien tunnel complex.
  • Natural History of Earth  - Text by ProxCenBound, M. Alan Kazlev, and Stephen Inniss
    The geological and biological history of Earth, the origin planet of Terragen life.
  • Old Earth  - Text by M. Alan Kazlev
    Generic term used to designate Earth before the Great Expulsion. As well as the literal meaning, and the reference to Terragen origins and ancient baseline history, the term has various other associated nuances, from the ridiculous or exaggerated to the romantic or sublime, including lost paradise, fool's opportunity, pre-archaiocractic human supremacy, unmoderated baseline civilization (positive or negative, depending on context and clade), natural evolution, and so on.
  • Paleolithic - Text by M. Alan Kazlev
    The old stone age. Among Old Earth hominids the stage of development of the most primitive stone tools. Also applied to analogous stages among xenosophont tool users.
  • Thyresta  - Text by Anders Sandberg
    Extinct alien species, inhabited Tawattaran (YTS-4885002-3825 IV; MPA).
  • Ultimates  - Text by Anders Sandberg and M. Alan Kazlev
    A static, genetically optimized phylum of sophonts inhabiting the Black Acropolis.
Related Topics
Development Notes
Text by Aaron Hamilton, M. Alan Kazlev, Steve Bowers
other timeline elements by various contributors
Initially published on 11 April 2003.

Pas'utu'ril information added 2022, from their 2020 update by radtech.
Additional Information