Distant past

16 billion years ago

 * The universe is formed in the instantaneous expansion that scientists call the "Big Bang". The "Big Bang" has been theorized to be caused by destabilizing Omega molecules.
 * This point in time represents a hideout for members of the Q Continuum. The USS Voyager was briefly transported here by Quinn in order to escape Q, but he too had once used this hideout and was thus able to find the ship.

9 billion years ago

 * Hundreds of protostars collapsed in close proximity to one another forming the astronomical phenomenon later known as a black cluster.

5 billion years ago

 * The star Sol begins to form out of nebular dust and interstellar gases.
 * is born.

4.5 billion years ago

 * The Guardian of Forever was asked its last question until 2267, when it told Captain James T. Kirk and Spock that it had awaited a question "since before your Sun burned hot in space."
 * The ancient humanoids, one of the oldest known sentient species, seeded the oceans of many worlds with DNA codes, directing the evolution of life towards a physical pattern similar to their own. The varieties of lifeforms that carried this seed code to fruition include the Humans, Vulcans, Klingons and Cardassians, and likely many other humanoid species of the galaxy.

4 billion years ago

 * Q and the female Q begin their romantic involvement around this time.
 * The planet Pollux IV forms in the Beta Geminorum system.

3.5 billion years ago

 * On Earth, in a region later known as France, amino acids combine to form the first proteins. In an alternate timeline, an anti-time eruption prevents the formation of life, fulfilling Q's verdict for Humanity.

2 billion years ago

 * Civilization on Tagus III exists as of this time. According to Q, they "really knew how to party back in those days".

1 billion years ago

 * The Slaver Empire is the master of all intelligent beings in the Milky Way Galaxy. The Slavers and all of their subjects are exterminated in a massive war which caused all intelligent life to re-evolve.

400 million years ago

 * In the Devonian period, Eryops, the last common ancestor of cold-blooded and warm-blooded organisms, lives on Earth.

300 million years ago

 * An alien ship of an insectoid race is invaded by a magnetic organism. Trapped in orbit of Questar M-17, the crew destroy their own ship to prevent it being carried to other worlds.

87 million years ago

 * The D'Arsay civilization launches the archive of their culture.

65 million years ago

 * A mass extinction occurs at the end of the Cretaceous period on Earth when an asteroid impacts the planet, wiping out the dominant reptile superorder, the dinosaurs, amongst others.
 * According to the Distant Origin Theory, some of Earth's dinosaurs belonging to the hadrosaur genus survive the mass extinction. Although the dominant reptile superorder was almost wiped out, these surviving dinosaurs continue to develop, likely on a secluded, later destroyed landmass. Sometime thereafter, they possibly become one of the first interstellar species in the galaxy when they leave Earth and travel to the Delta Quadrant, laying the foundation for the Voth civilization.

20 million years ago

 * Now considering themselves a race indigenous to the Delta Quadrant, the recorded history and identity of the Voth dates back to around this time.

5 million to 2.5 million years ago

 * The Pliocene epoch spans this time on Earth. Hanon IV had reached this level of geological evolution by the 24th century.

1 million years ago

 * On Earth, the ancestors of Humans begin to distinguish themselves from their primate ancestors by their intelligence and reasoning skills.
 * Construction of the vast city around the Guardian of Forever, stretching out to the horizon of its' planet.
 * Lactrans attain a level of development that would not be met in terms of Human development until the late 23rd century.

Indeterminate

 * The inhabitants of Organia evolve to beings of pure energy.

Hundreds of thousands of years ago

 * A -shaped lifeform that died in the mid-23rd century dates back to this era. It records everything it sees and experiences starting around this time as well, including data on countless civilizations

600,000 years ago

 * The Tkon Empire collapses.
 * The humanoid ancestors of Sargon's species colonize the galaxy. Their colonists may have caused, or influenced, the rise of intelligent life on.

500,000 years ago

 * Sargon's species is destroyed in a massive civil war when the atmosphere is ripped from their planet. Only a few survivors escape by preserving their consciousnesses in a cave deep below the surface.
 * Bajoran civilization begins to flourish. The ancient Bajorans are renowned for their accomplishments in science, mathematics, philosophy, and the arts long before Humans learn to speak or make tools.
 * The planet Exo III becomes uninhabitable after its sun begins to go dark. The inhabitants resettle beneath the surface and construct androids to serve them.

200,000 years ago

 * The Iconians, a highly developed civilization, are presumed destroyed in an orbital bombardment of their homeworld.
 * The large bioplasmic organism, later dubbed the "telepathic pitcher plant", is born in the Delta Quadrant.
 * By at least this point, as according to Q, the Borg have begun their evolution into cybernetic beings.

100,000 years ago

 * The subspace network which will be later claimed by the Hirogen is constructed.
 * The ocean planet, later home of the Monean civilization, is created by extracting all water from a class M planet and containing it inside an immense force field.
 * In Africa on Earth, the /Xam Abathwa tribe gathers to share a story about a girl who created the milky way.

50,000 years ago

 * The Horta of Janus VI begin their latest cycle of rebirth.
 * Bele begins to chase Lokai, who has led a revolution on the planet of Cheron.

45,000 years ago

 * Around 42,600 BC, extraterrestrial visitors, known as the "Sky Spirits", visit a people on Earth who become the indigenous inhabitants of South America.

30,000 years ago

 * The Verathan civilization, originally from the Verath system in the Gamma Quadrant, reaches its height, spanning two dozen star systems.
 * An ancient city is built on Bajor with walls and a stone tablet. Trapped inside the tablet are two antagonistic non-corporeal lifeforms, a Pah-wraith and a Prophet.

28,000 years ago

 * On Earth, the Neanderthals become extinct.

25,000 years ago

 * The stone tablet city in Bajor is abandoned, sediments bury the ruins, and eventually the ancient city of B'hala is built on top.

22,000 years ago

 * The first of at least 947 archaeological expeditions is conducted at the ancient ruins on Tagus III.
 * The Trill begin their life as a joined species.

20,000 years ago
Circa 17,627 BC to 17,600 BC
 * The Bajoran Holy City of B'hala is lost to history.
 * The Bajorans begin celebrating the Bajoran Gratitude Festival.

12,000 years ago

 * An artisan known only as the Master of Tarquin Hill on Kurl, during the, creates small ceramic figurines, called naiskos, that embody that culture's belief that within each person is a community of individuals, each with its own desires, views, and voices.

10,000 years ago

 * The machine-god Vaal on Gamma Trianguli VI is built.
 * The civilization on Sigma Draconis VI, by this point at its technological peak, advanced well beyond 23rd century Federation capabilities, experiences a catastrophic glacial age. As a result, the inhabitants of the planet begin to de-evolve to a primitive level, and the male and female inhabitants experience a great schism in their society.
 * When their sun is about to go nova, the Fabrini leave their system on a propelled asteroid known as Yonada.
 * A species of intelligent spacefaring organisms which form symbiotic relationships with humanoid lifeforms that live within their bodies becomes nearly extinct. Gomtuu is the last known survivor.
 * The first of the Orbs is discovered by the Bajorans in the sky above their planet. Over the next ten millennia, a total of nine of these extraordinary objects are discovered, inspiring revelations that shape Bajoran religion.
 * According to Quinn, this is the last time that "ordinary" Q in the Q Continuum have to speak with each other.
 * Bajoran archaeologists begin their unsuccessful search for the lost city of B'hala, which is not uncovered until the year 2373.
 * A path on a Delta Quadrant planet was said to be cut out by unknown spacefarers. The path endured into the 24th century, when it was used by Mikhal Travelers who had an outpost on the planet.

Indeterminate

 * The Custodian is built by the Progenitors on the planet Aldea.

9,000 years ago

 * The Zakdorn earn a reputation as brilliant strategists.

6,000 years ago

 * circa 4000 BC: Unknown aliens remove several Humans from Earth to be eugenically bred on a distant planet, lest Humanity destroy itself in its early technological age. Gary Seven, Agent 201 and Agent 347 will be among their descendants.
 * 3834 BC: Akharin is born in Mesopotamia on Earth. A soldier felled in battle, he soon realizes that no injury can kill him. He goes on through many aliases, becoming the immortal known as Flint.
 * circa 3733 BC: Landru of Beta III preaches peace and coexistence among his people, ending a period of savagery. He creates a powerful computer to guide and protect his people after his death.

5,000 years ago

 * circa 2700 BC: Earth is visited by aliens who settle in the region near Greece and the Mediterranean, where they are worshiped by the Greeks as gods.


 * Sarpeidon experiences an ice age. Zarabeth is later exiled to this time period, and Spock and Leonard McCoy are briefly stranded here as well.
 * By this time, Vulcans are still barbaric, war-like and "nearly killing themselves off with their own passions".


 * circa 2600 BC: The Egyptians build the pyramids of Giza. They are observed by anthropologists from the future (specifically, the year 2769).
 * A battle warm-up is developed, that according to legend, "makes the heart a friend to the hand."


 * circa 2500 BC: Vulcans begin to mentally train themselves to suppress their emotions.
 * Humans develop currency.

4,000 years ago

 * circa 1800 BC: The Xindi-Avians build a concealed fortress on a planet that will one day become the home of the Xindi Council.


 * circa 1735 BC: According to Spock, this is when Humans begin to glorify organized violence.
 * Humans on Earth begin the tradition of confining law-breakers to prisons.

3,000 – 2,000 years ago

 * circa 950 BC: Flint claims to live the life of King Solomon on Earth.
 * circa 850 BC: The Vulcan monastery on P'Jem is built.


 * circa 730 BC: The Kalandan outpost planet, "a few thousand years old" in 2268, may be constructed around this time.
 * circa 630 BC: The Bajoran prophet Trakor first encounters the Orb of Prophecy and Change, and writes a series of prophecies concerning the Emissary of the Prophets.
 * circa 525 BC: Aeschylus is born in Greece.
 * 480 BC: The Battle of Thermopylae is fought on Earth between the Spartans and the Persians.
 * circa 400 BC: Survivors from the Sahndara system supernova arrive on Earth. Their sojourn coincides with the time of the philosophers Socrates and Plato. "After the death of the Greek civilization they idolized" they move on to the planet Platonius.
 * 356-323 BC: Flint lives the life of Alexander the Great on Earth.
 * 280 BC: The Lighthouse of Alexandria is built under Ptolemy II.
 * 214 BC: Construction begins on the Great Wall of China on Earth.
 * 120 BC: Hipparchus dies.
 * 44 BC: Parmen, future leader of the Sahndaran refugee community, is born on.
 * circa 40s BC: The records data on Kaminar, indicating that a significant portion of Kelpiens have passed Vahar'ai to reach a more evolved state.
 * 32 BC: Philana, future wife of Parmen, is born on Sahndara.
 * 3 BC: Philana, now 30, stops aging.

Background information
The following events are from the fourth edition of the (vol. 1, pp.. 109, 143; vol. 2, pp. 103, 171, 395):
 * In 5th century Asia, Buddha founds the nontheistic religion of Buddhism.
 * Socrates is born in 469.
 * Plato is born in circa 428.
 * The Olmec civilization of Mexico ends in about 400.
 * Socrates dies in 399.
 * Plato dies in circa 348.
 * Cicero is born in 106.
 * Cicero dies in 43.

Indeterminate past

 * Eons ago the Changelings are Solids before they evolve into a liquid-based, shapeshifting species.
 * An unknown race, possibly of extragalactic origin, builds a massive planet killer.
 * The population of Talos IV is largely wiped out in a war thousands of centuries ago. Forced to live beneath the surface, the Talosians develop their mental powers, while neglecting their technological knowledge and skills.
 * According to Klingon mythology, Kortar, the first Klingon, destroys the gods who created him.
 * A neutron star in a binary star system in the Kavis Alpha sector begins exploding every 196 years.
 * A power struggle occurs within the highest ranks of a race called the Saltah'na, which ultimately destroys them. Before their extinction, the Saltah'na create a collection of energy spheres which preserve a record of the events leading to the species' destruction via a telepathic matrix, which can be transferred into the minds of some humanoid species, causing them to reenact the power struggle.
 * A scientist named Lazarus discovers the alternative warp, constructing a space-time vehicle which can transverse the corridor between two universes over both time and space. He begins his relentless pursuit of his nemesis "the thing" across centuries of time, who is in fact Lazarus's own from the alternate universe.
 * The people of Megas-Tu leave their dimension in search of companionship which they find initially on Earth.
 * According to Cosimo in an alternate 2372, Harry Kim could have been sent to before the formation of sentient life on Earth by the time stream, had his attempt to restore history failed. ()
 * In the Delos system, the two inhabited planets Ornara and Brekka took different paths, with Ornara becoming technologically sophiscated and Brekka not doing likewise.


 * The being known as Kevin Uxbridge, a Douwd, begins living in the Milky Way Galaxy.


 * The Mintakans of the planet Mintaka III abandon their in the supernatural.