Timeline of Star Trek

• The Big Bang
  • Quinn hides in the big bang to avoid discovery by Q.[2]
• c. 6 billion years ago
  • The Guardian of Forever is formed.[3]
• c. 4 billion years ago
  • A humanoid civilization seeds the oceans of many planets with genetic material, which would lead to the development of humanoids on many planets.[4]
• c. 65 to 100 million years ago
  • The dinosaurs (the Voth civilization) from the episode "Distant Origin" are most likely descendants of Hadrosaurids who lived in the Cretaceous period of Earth's history.
• c. 1 million years ago
  • Sargon's people explore the galaxy and colonize various planets, possibly including Vulcan.[5]
• c. 600,000 years ago
  • The Tkon Empire, an interstellar state consisting of dozens of star systems in the Alpha Quadrant, becomes extinct.
• c. 200,000 years ago
  • The Iconian civilization is destroyed.
• c. 8,000 BCE
  • The Dominion may have been founded in the Gamma Quadrant by the shapeshifting race known as the Changelings around this time, possibly in a different form than is known in the modern timeline.[6]
• c. 2700 BCE
  • A group of extraterrestrial beings landed on Earth and was eventually known as the Greek gods established in the episode "Who Mourns for Adonais?".

• c. 4th century CE
  • The Vulcan Time of Awakening. In the midst of horrific wars on Vulcan, the philosopher Surak leads his people, teaching them to embrace logic and suppress all emotion.[7]
  • The Dominion may have been founded in the Gamma Quadrant by the shapeshifting race known as the Changelings (founders) around this time.[8]
• c. 9th century
  • Kahless the Unforgettable unites the Klingons by defeating the tyrant Molor in battle, and provides his people with teachings based on a philosophy of honor.[9]

• c. 1505
  • The Borg are known to exist in the Delta Quadrant, 900 year prior to Voyager landing on the planet. As referenced by the Vaadwaur. "Dragon's Teeth" (VOY)
• c. 1570
  • The ancient Bajorans use solar sail ships to explore their star system, and one may have reached Cardassia.[10]
• 18th century
  • The Suliban homeworld becomes uninhabitable. ("Detained" (ENT))
  • The Preservers transport various Native Americans to a far-away planet.[11]
• c. 1864
  • The Skagarans abduct humans for use as slaves in their colony world. (as referred to in Enterprise Season 3: North Star)
• c. 1871
  • The Cardassian Union is established.[12]
• 1888
  • August 31 – Jack the Ripper's first victim is found murdered and mutilated in East London. (as referred to in Star Trek: The Original Series Season 2: "Wolf in the Fold")
• c. 1893
  • "Time's Arrow" (TNG)

• 1918
  • World War I ends with 6 million dead. "Bread and Circuses (TOS)"
• 1930
  • "The City on the Edge of Forever" (TOS)
• 1937
  • Several hundred humans are secretly abducted by an alien race known as the Briori and brought to the Delta Quadrant. Eight are cryogenically frozen, including long-lost pilot Amelia Earhart. "The 37's" (VOY)
• 1944
  • "Storm Front" (ENT)
• 1945
  • World War II ends with 11 million dead. "Bread and Circuses (TOS)"
• 1947
  • Three Ferengi (Quark, Rom, and Nog) crash land in the New Mexico desert, and are held by the U.S. government at a secret base for scientific study. "Little Green Men" (DS9)
• 1957
  • A Vulcan scout ship visits Earth, according to a story told by T'Pol (presumably a true story as T'Pol examines a purse which was portrayed as used by her great-great-grandmother during the story; see episode entry). "Carbon Creek" (ENT)
• 1967
  • Captain Braxton's 29th century Federation timeship Aeon crashlands on Earth. "Future's End" (Voyager)
• 1968
  • "Assignment: Earth" (TOS)
• 1969
  • "Tomorrow Is Yesterday" (TOS)
• 1986 –
  • Star Trek IV: The Voyage Home
• 1992
  • The Eugenics Wars (WWIII) begin.[13] (WWIII is retconned to be in 2050s by TNG's Encounter at Farpoint and Star Trek First Contact; DS9's "Doctor Bashir, I Presume?" retcons the Eugenics Wars as being in the 22nd century)
• 1996
  • The Eugenics Wars end.[13] (WWIII is retconned to be in 2050s by TNG's Encounter at Farpoint and Star Trek First Contact; DS9's "Doctor Bashir, I Presume?" retcons the Eugenics Wars as being in the 22nd century)
  • "Future's End" (VOY)
  • the SS Botany Bay is stolen by a group of about 80 or 90 augments "Space Seed" (TOS)
• 1999
  • Voyager 6 is launched[14]

• 2000
  • The past events of "11:59" (VOY).
• 2002
  • The interstellar probe Nomad is launched.[1][15]
• 2004
  • The past events of "Carpenter Street" (ENT).
• 2009
  • The first successful Earth-Saturn probe takes place.[1][16]
• 2012
  • The world's first self-sustaining civic environment, Millennium Gate, which became the model for the first habitat on Mars, completed in Portage Creek, Indiana. ("11:59", Voyager)
• 2018
  • Sleeper ships are made obsolete.[17]
• 2024
  • A united Ireland is achieved by republican terrorists (TNG "The High Ground")
  • The past events of "Past Tense" (DS9). Namely the "Bell Riots".
• 2032
  • Ares IV, a manned mission to Mars is launched.[18]
  • Zefram Cochrane is born
• 2037
  • The spaceship Charybdis makes an attempt to leave the solar system.[19]
• 2053
  • World War III ends and Earth is left devastated, mostly because of nuclear warfare. Scientific advancement continues, however.[20] (In TOS WWIII took place in the 1990s[13] while DS9's "Doctor Bashir, I Presume?" had the Eugenics Wars in the 22nd century)
• 2063
  • The past events of Star Trek: First Contact. Zefram Cochrane makes the first human warp flight with the Phoenix. This attracts the Vulcans and they make first contact with humans. (TOS Metamorphosis stated that Zefram Cochrane disappeared 150 years ago at the age of 87 which fits with the current timeline).
• c. 2065
  • The SS Valiant is launched.[1][21]
• 2067
  • The unmanned interstellar warp probe Friendship 1 is launched[22]
• 2069
  • The colony ship SS Conestoga is launched. It would found the Terra Nova colony.[23]
• 2079
  • Earth begins to recover from its nuclear war.[24] The recovery is aided and partially organized by a newly established political entity called the European Hegemony.[1]
• 2088
  • T'Pol is born

• 2103
  • Earth colonizes Mars
• 2111
  • Jonathan Archer is born in upstate New York on Earth.[25]
• 2119
  • Zefram Cochrane, who now is residing on Alpha Centauri, sets off for parts unknown and disappears. Some thought he was testing a new engine. After an exhaustive search, it is believed that Cochrane has died. He becomes one of the most famous missing people in history.[26]
• 2129
  • Hoshi Sato is born.[25]
• 2142
  • Warp 2 Barrier broken by Commander Robinson in NX Alpha and Warp 2.5 achieved by Commander Archer in NX Beta
• 2145
  • Warp 3 Broken by Commander Duvall in NX Delta
• 2150
  • Keel laid for Enterprise (NX-01)
• 2151–2155
  • The events of Star Trek: Enterprise take place.[27]
• 2156–2160
  • The Earth–Romulan War is fought between United Earth and its allies, and the Romulan Star Empire. The war ends in a stalemate though the Romulans are defeated at the Battle of Cheron. The Romulan Neutral Zone is established.[1]
• 2161
  • The United Federation of Planets is founded by Earth, Tellar, Andoria, and Vulcan.[28][29]
• 2165
  • Sarek, Federation diplomat and father of Spock, is born on Vulcan.[30]
• 2160s to 2196
  • The Daedalus class starship is active.[31]

• 2222
  • Montgomery Scott is born in Scotland.[32]
• 2226
  • Michael Burnham is born on Earth.[33]
• 2227
  • Leonard McCoy is born in Georgia, North America on Earth.[34]
• 2230
  • Spock, the son of Sarek and the human Amanda Grayson, is born on Vulcan.[35]
  • Hikaru Sulu is born in San Francisco, North America on Earth.[36]
• 2233
  • James T. Kirk is born in Riverside, Iowa on Earth.[37]
• 2233 (alternate timeline)
  • James T. Kirk is born aboard a shuttlecraft from the USS Kelvin.
  • James T. Kirk's father, George Kirk, is killed.
  • Nyota Uhura is born in the United States of Africa.[38] This fits with the alternate timeline, unlike her alternate birth date of 2239, for the latter would suggest her only being nineteen in the film.
• 2241 (alternate timeline)
  • Pavel Chekov born in Russia on Earth
• 2245–2250
  • The USS Enterprise, a Constitution class vessel is launched under the command of Robert April, on a five-year mission of exploration.[1] In the alternate timeline created by Nero's attack on the USS Kelvin, the Enterprise is still under construction in 2255 and is not launched on her maiden voyage until 2258.
• 2245
  • Pavel Chekov is born to Russian parents.[39] In the alternate timeline created by Nero's attack on the USS Kelvin, Chekov is only eight years younger than James T. Kirk, implying a birthdate of 2241.[40]
• 2250
  • After a refit, the USS Enterprise (NCC-1701) is launched on a second five-year mission. Command of the ship is assigned to Captain Christopher Pike.[1]
• 2254
  • The events of "The Cage".[41]
• 2256-2257
  • The events of Star Trek: Discovery season 1 take place.
• 2257-2258
  • The events of Star Trek: Discovery season 2 take place. The USS Discovery & USS Enterprise (NCC-1701) engage in a pitched battle to neutralise the rogue AI Control. The battle is a success, however the Enterprise falsely reports that the Discovery was lost with all hands to conceal the fact that it travelled 930 years into the future in order to prevent Control from reasserting itself. The Enterprise subsequently undergoes repairs and departs for Edrin II 4 months later.
• 2258 (alternate timeline)
  • The events of Star Trek take place. Nero destroys the planet Vulcan – killing billions, including Spock's mother – as well as 9 Federation starships. The USS Enterprise (NCC-1701) is launched on her maiden voyage under Captain Christopher Pike. James T. Kirk becomes the ship's new captain shortly afterward. Henceforth, a different timeline is required.
• 2259 (alternate timeline)
  • The events of Star Trek Into Darkness take place.
• 2260 (alternate timeline)
  • The Enterprise is launched on a historic five-year mission.
• 2263 (alternate timeline)
  • The events of Star Trek Beyond take place. The USS Enterprise is destroyed – The USS Enterprise-A is commissioned at Starbase Yorktown as its replacement.
  • Ambassador Spock dies.
• 2261–2264
  • The USS Enterprise (NCC-1701) undergoes a major refit, increasing its crew complement from 203 to 430.[1]
• 2263
  • Boothby, groundskeeper and counselor at Starfleet Academy, is born.
• 2265–2270
  • Following the promotion of Christopher Pike, Captain James T. Kirk is assigned command of the Enterprise on a historic five-year mission.[1] (In the originally canonal Star Trek Spaceflight Chronology this was 2207 to 2212)
• 2265
  • The events of "Where No Man Has Gone Before".
• 2266–2269
  • The events of Star Trek: The Original Series take place.
• 2269-2270
  • The events of Star Trek: The Animated Series take place.
• 2270
  • The USS Enterprise (NCC-1701) returns from its five-year mission under the command of Captain James T. Kirk and enters major refit while Kirk is promoted to Admiral at Starfleet Command.
• 2273
  • The events of Star Trek: The Motion Picture.
• 2273-2278
  • The upgraded USS Enterprise (NCC-1701) embarks on a five-year mission under the command of Admiral James T. Kirk.[1]
• 2279
  • Around this time the USS Enterprise (NCC-1701) is retired from active duty and assigned as a training vessel in orbit of Earth.[1]
• 2285
  • The events of Star Trek II: The Wrath of Khan.
  • The events of Star Trek III: The Search for Spock. The USS Enterprise (NCC-1701) is destroyed to prevent it from falling into Klingon hands.
• 2286
  • The events of Star Trek IV: The Voyage Home.
  • The newly refit USS Yorktown (NCC-1717) is renamed the USS Enterprise (NCC-1701-A) and is launched on its maiden voyage.
• 2287
  • The events of Star Trek V: The Final Frontier. (Note that this film apparently takes place soon after the events of the fourth film, as evidenced by Scotty's complaints about repairing the ship after its shakedown cruise, which was depicted at the end of Star Trek IV. Star Trek V would then take place in early 2287, with the events of Star Trek IV spanning most of 2286, with several months passing after Kirk's return to the future to account for the preparation of the Enterprise-A and Gillian's training for her space assignment.)
• 2293
  • The events of Star Trek VI: The Undiscovered Country. The Enterprise-A is slated to be decommissioned shortly afterwards.
  • The opening events of Star Trek Generations. The USS Enterprise (NCC-1701-B) is launched under the command of John Harriman. While responding to a distress call, the Enterprise is struck by a discharge from the Nexus which breaches the hull and James T. Kirk is presumed killed in the blast.

• 2305
  • Jean-Luc Picard is born in LaBarre, France on Earth.[42]
• 2311
  • The Tomed Incident.[1][43]
• 2324
  • Beverly Howard (Crusher) is born in Copernicus City, Luna.[42]
• 2327
  • Jean-Luc Picard graduates from Starfleet Academy on Earth (2323-2327).
• 2332
  • Benjamin L. Sisko is born in New Orleans, Louisiana on Earth.[1]
• 2333
  • Jean-Luc Picard becomes captain of the USS Stargazer.[1]
• 2335
  • Geordi La Forge is born in the African Federation, Earth[42]
  • William T. Riker is born in Valdez, Alaska on Earth.[1]
• 2336
  • Deanna Troi is born on Betazed.[42]
  • Kathryn Janeway is born in Bloomington, Indiana on Earth.[44]
• 2337
  • Tasha Yar is born in a failed Federation colony on Turkana IV.[1]
• 2340
  • Worf, son of Mogh, is born on the Klingon homeworld, Qo'noS.[1][45]
• 2341
  • Julian Bashir is born.[46]
• 2343
  • The Galaxy class development project is officially given the greenlight by Starfleet Command.[47]
• 2344
  • The Enterprise-C, under the command of Captain Rachel Garrett, is destroyed defending a Klingon settlement on Narendra III under attack from Romulans.[1][48]
  • Due to the Enterprise-C's sacrifice, a new era of more open communication begins between the Federation and the Klingon Empire, leading to a formalized alliance.
• 2345
  • Sela (half-romulan/half-human), daughter of Natasha Yar (alternate reality from "Yesterday's Enterprise") is born.
• 2346
  • Worf's parents are killed by Romulans in the Khitomer massacre. Worf (age 6) is adopted by human parents.[1][49]
• 2349
  • Annika Hansen is born in Tendara Colony, to Magnus and Erin Hansen.
• 2355
  • Magnus, Erin, and Annika Hansen are assimilated by the Borg while on a research mission in the Delta quadrant.
• 2357
  • Worf is the first Klingon to enter Starfleet Academy.[1]
  • USS Galaxy (NX-70637), the prototype Galaxy class is launched.[47]
• 2363
  • USS Enterprise (NCC-1701-D), the third Galaxy class starship (Following the Galaxy and Yamato) is launched from the Utopia Planitia shipyards in Mars orbit (under the command of Jean-Luc Picard), and becomes the Federation's new flagship.
• 2364–2370
  • The events of Star Trek: The Next Generation.
• 2367
  • The Borg assimilate Captain Jean-Luc Picard – the Battle of Wolf 359 is fought 7.7 light years from Earth in Sector 001. The battle results in the loss of 39 Starfleet vessels and over 11,000 lives. Benjamin Sisko aboard the USS Saratoga was a participant in the battle and was one of the few survivors alongside his son Jake Sisko. With the task force lost, the Borg continue to Earth. Picard is rescued and the Borg cube is destroyed via the actions of the crew of the Enterprise-D.
• 2369–2375
  • The events of Star Trek: Deep Space Nine.
• 2370
  • The USS Defiant (NX-74205), a mothballed prototype originally designed to fight the Borg, is commissioned into active service and is assigned to Benjamin Sisko to help protect DS9. Due to the Defiant being over-powered and over-gunned for its size, several flaws in the ship's design require attention before it reaches a fully operational status. The Defiant is officially classed as an escort vessel, however unofficially it is considered a warship built purely for combat.
• 2371
  • The events of Star Trek Generations. The USS Enterprise (NCC-1701-D) is destroyed – the stardrive section by a warp core breach; the saucer section containing the crew makes a forced landing on Veridian III. The ship is subsequently declared a total loss. James T. Kirk reappears from the temporal continuum in which he had been since his disappearance in 2293; Kirk is killed on Veridian III (Kirk is resurrected a month later in a subsequent story written by William Shatner, called The Return ).
• 2371–2378
  • The events of Star Trek: Voyager.
  • "Caretaker": the USS Voyager is stranded in the Delta Quadrant.
• 2372
  • Sovereign-class USS Enterprise (NCC-1701-E) launched under the command of Captain Jean-Luc Picard
• 2373
  • The events of Star Trek: First Contact. The Battle of Sector 001 occurs with a Starfleet Task Force engaging in a running battle with a Borg cube en-route to Earth. The USS Enterprise (NCC-1701-E) follows a Borg sphere through a temporal rift and events shift at that point to 2063.
  • Still unaware that the USS Voyager is stuck in the Delta Quadrant, Starfleet officially declares the ship lost with all hands.
• 2373–2375
  • Tensions between the Alpha and Gamma quadrants erupt into open warfare, igniting the Dominion War fully.
• 2375
  • The USS Defiant (NX-74205) is destroyed. Several weeks later, DS9 receives a replacement Defiant Class vessel, the USS Sáo Paulo. Captain Sisko is granted special permission by Starfleet to rename the vessel to Defiant.
  • After devastating losses on both sides, The Federation, alongside the Romulan and Klingon Empire make a final push against the Dominion resulting in the Battle of Cardassia. The Dominion subsequently surrenders to the Federation.
  • The events of Star Trek: Insurrection.[50] Dialogue in this film and in the DS9 finale "What You Leave Behind" place the chronology of this film as during that episode, after the final battle of the war but before the treaty signing ceremony. Most notable in the film is Worf's ability to leave the station to join the Enterprise, as well as a line about Federation diplomats being involved in Dominion negotiations, and the Federation's willingness to work with the Son'a, who are established as a Dominion ally during the war.
• 2378
  • With the help of Admiral Janeway, the USS Voyager returns to the Alpha Quadrant. ("Endgame"). Tom Paris' and B'Elanna Torres's daughter was born.
• 2379
  • The events of Star Trek: Nemesis, resulting in the death of Lieutenant Commander Data.[51]
  • Discovery of previously unknown Android named "B-4", a prototype android similar in design to Lt. Commander Data but with a notably less advanced Positronic Network.
• 2385, First Contact Day
  • The Utopia Planitia Fleetyards on Mars are sabotaged and subsequently destroyed by rogue synthetics in a surprise attack. The battle results in the loss of 92,143 lives, the planet itself being considered destroyed as the stratosphere was ignited and the destruction of the rescue armada to evacuate Romulus. In the aftermath of the attack, the Federation, unable to determine how or why the synths went rogue, bans the creation of synthetic lifeforms.
• 2386
  • Lieutenant Icheb is captured and stripped for his Borg parts by Bjayzl, and subsequently euthanized by Seven of Nine.
• 2387
  • A star in the Romulan Empire goes Supernova. Ambassador Spock attempts to counter the resulting shockwave using Red Matter, but is unable to save the planet Romulus from destruction. Spock and a Romulan ship commanded by Nero are dragged into a black hole created by the Red Matter detonation and arrive in the past. Nero's arrival in 2233 and subsequent attack on the USS Kelvin creates the Kelvin Timeline.
• 2394
  • Voyager returns to the Alpha Quadrant in the beginning of Star Trek: Voyager series finale ("Endgame"). This sets in motion events which Kathryn Janeway becomes dissatisfied with and begins laying plans to eventually change the timeline and send Voyager home sooner.
• 2395
  • The "Future" in the Star Trek: The Next Generation series finale ("All Good Things...")
• 2399–(TBD)
  • The events of Star Trek: Picard.[52]

• 2404
  • The original timeline split in the Star Trek: Voyager series finale (Endgame), where Admiral Janeway goes back 26 years to the Delta Quadrant and secures Voyager's earlier return to the Alpha Quadrant. This begins a new timeline (as yet unnamed).

• c. 2540–2550
  • The Starship Enterprise-J (presumably NCC 1701-J) is commissioned and takes part in the Battle of Procyon V against the Spherebuilders as shown in Enterprise episode "Azati Prime".

• Temporal Cold War (with agents from the 31st century) – First established in the pilot episode of Star Trek: Enterprise and recurring until the series' fourth season premiere, it is a struggle between those who would alter history to suit their own ends and those who would preserve the integrity of the original timeline.

• The Aeon-type timeship is in active service during this century, ("Future's End") as is the Wells-class timeship Relativity. ("Relativity")

• The main plot of the Star Trek: Voyager episode "Living Witness" takes place sometime around 3074, and the final scene takes place "many years" after that.

• Episodes with time traveler Daniels from Enterprise
  • "Cold Front", "Shockwave", "Azati Prime"

• 3186
  • This is the year Gabrielle Burnham arrived in after using the Red Angel suit to escape a Klingon attack on her home. (Discovery S2 E10)
  • This is the same year Star Trek: Discovery season 3 will be set.[53]

• Star Trek: Short Treks episode "Calypso" takes place sometime during this century. By Star Trek's fictional chronology, this is the last episode of all the seven series.

Not many references set the original series in an exact time frame, and those that exist are largely contradictory. In the episode "Tomorrow Is Yesterday", a 1960s military officer says that he's going to lock Captain Kirk up "for two hundred years", to which Kirk replies, with wry amusement: "That ought to be just about right." Likewise, in the episode "Space Seed", it is said that the 1996 warlord Khan Noonian Singh is from "two centuries" ago. Both these references place the show in the 22nd century. However, in the episode "Miri", it is said that 1960 was around 300 years ago, pushing the show into the 23rd century. Finally, the episode "The Squire of Gothos" implied that the light cone of 19th century Earth has expanded to 900 light years of radius, which seems to set the show in the 28th century, since light would take nine centuries to traverse that distance.

According to notes in The Making of Star Trek, the show is set in the 23rd century, and the Enterprise was supposed to be around 40 years old. Roddenberry says in this book that the stardate system was invented to avoid pinning down the show precisely in time frame.[55] Roddenberry's original pitch for the series dated it "'somewhere in the future. It could be 1995, or maybe even 2995".[56]

The Star Trek Spaceflight Chronology and FASA, a publisher of the first licensed Star Trek role-playing game, chose to take the "Space Seed figure", adding a few years to make sure the events of the Original Series were in the 23rd century. This dating system is followed by other spin-off works in the 1980s, including Mr. Scott's Guide to the Enterprise. This timeline system gives the following dates[57][58]

• The sub-warp ship the UNSS Icarus makes first contact with Alpha Centauri in 2048, and there meets Zefrem Cochran [sic], who has invented warp drive.[57]
• The first Earth warp ship, the Bonaventure makes its first voyage, to Tau Ceti, in 2059.[57]
• The first contact with Vulcans is in 2063.[57]
• The Federation is formed in 2087.[57]
• The Earth–Romulan War occurs in the 2100s.[57]
• First contact with the Klingon Empire in 2151.[57]
• The first Constitution-class starship is launched in 2188.[57]
• The USS Enterprise's five-year mission under Captain Kirk lasts from 2207 to 2212.[58]
• The events of Star Trek: The Motion Picture occur in 2217.[58]
• The events of Star Trek II: The Wrath of Khan occur around 2222 (dialogue in the film says it is set "fifteen years" after the Season One episode "Space Seed").
• The events of Star Trek IV: The Voyage Home occur on September 21, 2222.[58]

The Star Fleet Battles game was published in 1979, with a license only covering the original series. It has since diverged into an entirely separate fictional universe, new additions to which continue to be published. It does not tie into the Gregorian calendar, instead using a "Year 1" of the invention of Warp on earth. Its version of the original series backstory is:

• Y1 – Warp drive is developed on Earth.
• Y4 – Federation is formed by Earth, Vulcan, Andoria, Alpha Centauri.
• Y40-Y46 – Earth–Romulan War.
• Y71 – Starfleet is formed.
• Y126 – The Constitution-class is launched (an upgrade from the Republic-class).
• Y154–159 – The events of the Original Series.

See Star Fleet Universe timeline.

Press materials for The Next Generation suggested it was set in the 24th century, seventy-eight years after the existing Star Trek, although the exact time frame had not yet been set in stone. The pilot had dialogue stating Data was part of the Starfleet "class of '78".[59] The pilot episode, "Encounter at Farpoint", also has a cameo appearance by Leonard "Bones" McCoy, who is said to be 137.

In the last episode of the first season, the year is firmly established by Data, as 2364.[59] This marked the first time an explicit future calendar date had been attached to a Star Trek storyline, and allowed fans and writers to extrapolate further dates. For example, the established date implies McCoy was born around 2227, ruling out the Spaceflight Chronology-derived dating of the original series to the early 23rd century (though the dating had already been effectively overruled by Star Trek IV, which primarily takes place in 1986, where Kirk tells Gillian Taylor that he is from the late 23rd Century, though he does not give an exact date).

A Star Trek Chronology was published in 1993, written by production staff members Denise Okuda and Michael Okuda.[60] A second edition was issued in 1996.[1] Okuda originally drew up a timeline for internal use by writers, based on his own research and assumptions provided by Richard Arnold. The dates in the Chronology are consistent with the earlier Star Trek: The Next Generation Technical Manual.[47]

It gives the following dates:

• Zephram Cochrane invents warp drive around 2061 (so that the SS Valiant can be constructed and go missing two hundred years before "Where No Man Has Gone Before", dated to 2265; the first edition gives 2061, the second edition moves this to 2063 per Star Trek: First Contact)
• the Romulan War takes place in the 2150s (about a hundred years before "Balance of Terror")
• the Federation is formed in 2161, after the Romulan War, on the basis that "Balance of Terror" says that it was an Earth-Romulan war, not a Federation-Romulan War
• the first Constitution class starship is launched in 2244, followed by the Enterprise in 2245
• Kirk's five-year mission lasts from 2264 to 2269, based on the assumption that the original series is set exactly 300 years after its original broadcast.
  • aired live-action Star Trek episodes are dated from 2266 to 2269. The chronology does not include the events of Star Trek: The Animated Series. This is in keeping also with Gene Roddenberry's concept (discussed in The Making of Star Trek by Roddenberry and Stephen Whitfield) that Star Trek's first season takes place after the mission has been under way for some time.
  • An episode of Voyager—"Q2"—, aired after the Chronology was published, established that Kirk's five-year mission actually ended in 2270.
• the events of Star Trek: The Motion Picture take place in 2271 (Kirk has been Chief of Starfleet Operations for two-and-a-half years, according to dialog from Kirk and Decker)
  • The "Q2" dating for Kirk's five-year mission, moves the first film to c. 2273.
• Numerous sources, including the Chronology, postulate a second five-year mission under now-Admiral Kirk's command began soon after the events of the first movie; in part this is to take into account the unproduced revival series Star Trek: Phase II.
• the events of Star Trek II: The Wrath of Khan and Star Trek III: The Search for Spock take place in 2285
  • The Wrath of Khan is a sequel to the episode "Space Seed", which Okuda dates to 2267. In Okuda's timeline there is a gap of eighteen years rather than the fifteen years established in dialog. The film was released in 1982, fifteen years after the episode's broadcast in 1967. The film begins on Kirk's birthday, which is semi-canonically established as March 22, the same as William Shatner.
• the events of Star Trek IV: The Voyage Home take place in 2286
  • This places Star Trek III in late 2285, as Kirk states in his log that the Enterprise crew has been on Vulcan for "three months" since bringing Spock home
• the events of Star Trek V: The Final Frontier take place in 2287
• the events Star Trek VI: The Undiscovered Country take place in 2293, based on McCoy's statement that he had served on the Enterprise for 27 years, and his absence in "Where No Man Has Gone Before"
• The Kirk-era part of Star Trek Generations is set 78 years before 2371 (established by way of an on-screen caption), thus is set in 2293 and soon after Star Trek VI

The gap between the 1986 film Star Trek IV: the Voyage Home (2286) and the 1987 first season of The Next Generation (2364) is 78 years by this timeline, matching early press materials.

A gap of 10 years passed between the broadcast of the last episode of Star Trek: The Original Series and the release of The Motion Picture. The film skirted around the fact the actors had aged, supposing that only two and a half years had passed since the events of the TV show. For Star Trek II, it was decided to acknowledge the reality of the aging actors, both by setting the film some 15 years after "Space Seed", and by having Kirk worry about getting old.[61]

Within The Next Generation era, episodes and films are easier to date. Stardates correspond exactly with seasons, with the first two digits of the stardate representing the season number. Okuda assumes the start of a season is January 1 and the end of the season is December 31.[1] The Next Generation, Deep Space Nine, and Voyager television series, as well as the movies, have roughly followed "real time", and are set around 377 years after their release.

Since the Chronology was published, it has been generally adhered to by the producers of the show. The film Star Trek: First Contact and prequel series Star Trek: Enterprise both revisit the early era. In First Contact, Zephram Cochrane is confirmed as having invented warp drive on Earth, but the date is moved forward slightly to 2063, and it is revealed that Earth's official first contact with an alien species, the Vulcans, took place immediately afterwards as a result of this.

The dating of the final season of Star Trek: Voyager has presented controversy. The standard assumption about stardates, as well as the regular correspondence between seasons and in-universe years, would place the entire season in the year 2377—the season begins with stardate 54014.4 and ends with 54973.4. However, the episode "Homestead" features a celebration of the 315th anniversary of Zefram Cochrane's first contact with the Vulcans, which would set the episode on April 5, 2378. The fansite Memory Alpha thus places the final eight episodes of the season ("Human Error" through "Endgame") in 2378, with other sources following suit.

Enterprise is set in the 2150s, and ties into the Cochrane backstory. The show uses the Gregorian calendar instead of Stardates, making tracking the dating easier. Its pilot, "Broken Bow", depicts first contact with the Klingons occurring much earlier than the Okuda chronology anticipated (it suggested a date of 2218, based on a line in "Day of the Dove", noting that dialog in "First Contact" makes this problematic – though the actual line in the episode referred to hostilities between the two, and in Enterprise Human-Klingon relations, while by no means friendly, clearly do not rise to the de facto state of war shown in TOS). It shows the opening of the Romulan war and the start of a coalition between Earth, Vulcan, Andor, and Tellar in the 2150s. The date of the founding year of the Federation, 2161, was revealed in the fifth-season TNG episode "The Outcast," based on an early draft of the Okuda timeline. The final episode of Enterprise, "These Are the Voyages...", is consistent with the establishment of 2161 as the founding year for the Federation.

No version of the Chronology or the Encyclopedia has been published since 1999. A 2006 book by Jeff Ayers contains a timeline which attempts to date all of the many Star Trek novels.[62] This timeline has The Motion Picture in 2273, to account for the two-and-a-half-year gap between the end-date of 2270 established in "Q2" and the events of the movie. The official website, StarTrek.com, still gives the date of that movie as 2271.[63]

When the original series of Star Trek was produced, the 1990s were several decades away, and so various elements of the backstory to Star Trek are set in that era, particularly the Eugenics Wars. The references to the Eugenics Wars and to a nuclear war in the 21st century are somewhat contradictory.

The episode "Space Seed" establishes the Eugenics Wars, and has them lasting from 1992 to 1996. The Eugenics Wars are described as a global conflict in which the progeny of a human genetic engineering project, most notably Khan Noonien Singh, established themselves as supermen and attempted world domination. Spock calls them "the last of your so-called World Wars", and McCoy identifies this with the Eugenics Wars.

In the episode "Bread and Circuses", Spock gives a death toll for World War III of 37 million. The episode "The Savage Curtain" features a Colonel Phillip Green, who led a genocidal war in the 21st century. The TNG episode "Encounter at Farpoint" further establishes a "post-atomic horror" on Earth in 2079. However, the movie Star Trek: First Contact put the contact between Vulcans and humans at April 5, 2063.

The Star Trek Concordance identifies the "Bread and Circuses" figure as the death toll for a nuclear World War III, in the mid-21st century. Star Trek: First Contact firmly establishes World War III ended, after a nuclear exchange, in 2053, but with a body count of 600 million. The figure of Colonel Green is elaborated on in Star Trek: Enterprise. First Contact also deliberately describes the warring parties in World War III as "factions", not nations per se.

The Voyager episode "Future's End" saw the Voyager crew time-travel to Los Angeles in 1996, which, as the Encyclopedia notes, seems entirely unaffected by the Eugenics Wars, which ended that year. The episode acknowledges the issue only by featuring a model of Khan's DY-100-class ship on a 1996 desk.[64] Khan's spaceship is another anomaly for the timeline, which has a variety of long-lost spaceships being launched between 1980 and 2100, with inconsistent levels of technology (caused by the increasing real lifetime and also decreased optimism about the pace of space exploration).

A reference in the Deep Space Nine episode "Doctor Bashir, I Presume?" suggests that the Eugenic Wars instead took place in the 22nd century. According to writer Ronald D. Moore, this was not an attempt at a retcon, but a mistake – when writing the episode, he recalled the already questionable "two centuries ago" line from "Space Seed" and forgot that DS9 takes place over 100 years later.[65]

Season 4 of Star Trek: Enterprise involves a trilogy of episodes ("Borderland" "Cold Station 12", and "The Augments") related to scientist Doctor Arik Soong, ancestor of Doctor Noonien Soong, and his genetic augmentations of Humans. Numerous historical details of the devastating Eugenics Wars are discussed: the death of 35–37 million people; how Earth's governments could not decide on the fate of the 1,800 genetically enhanced embryos; and how Soong had infiltrated the complex and stolen and raised 19 embryos himself. Soong maintained that he himself and humanity in general had learned the lessons of the Eugenics Wars and should not continue to hide behind those events when there was progress to be made now that the technology had matured and was much more practicable. (The actions of his "children" convince him otherwise, and at the end of "The Augments" Soong declares his interest in cybernetics, beginning the work which would one day bring about Data.)

Greg Cox's two-book series The Eugenics Wars: The Rise and Fall of Khan Noonien Singh develops the idea of the Eugenics Wars in the context of real-life history by representing it as a secret history, and that the truth behind the various civil wars and conflicts in the 1990s was not generally known; Los Angeles, whose appearance in "Future's End" helped bring the war's existence into question, is portrayed as an EW "battlefront", the Rodney King riots being one such calamity.

In the episode "Metamorphosis", it is stated that Zefram Cochrane of Alpha Centauri, the discoverer of the space warp, disappeared 150 years ago, at the age of 87. Given Okuda's date of 2267 for that episode, this puts Cochrane's disappearance in 2117 and birth in 2030. 1980s spin-off material such as the Star Trek Spaceflight Chronology posit that Cochrane was from Alpha Centauri originally, and that a sub-warp ship the UNSS Icarus arrived at Alpha Centauri in 2048 to find he had discovered the theory behind warp drive. The Icarus then relayed its findings back to Earth, the first prototype warp ship was launched in 2055.

The Star Trek Chronology does not hold with this theory, and asserts that Cochrane was an Earth native, who moved to Alpha Centauri later in life (even in "Metamorphosis", before Cochrane identifying himself to the landing party, Dr. McCoy had taken a tricorder scan and determined him to be human). The first edition Chronology notes that Cochrane's invention of warp drive must have been at least 200 years before "Where No Man Has Gone Before", and suggests a date of 2061, noting that Cochrane would be 31 that year.

The film Star Trek: First Contact prominently features Cochrane's first successful warp flight. The film is set in 2063, two years after the Chronology suggestions, and therefore by the timeline Cochrane is 33. The actor who played Cochrane in that movie, James Cromwell, was 56 at the time of the film's release. The Encyclopedia notes the age issue, and claims that the Cromwell Cochrane had suffered from radiation poisoning, causing his aged appearance. Enterprise pins down Cochrane's disappearance to 2119, making Cochrane instead 31 at the time of First Contact.