Timeline - Alternate Timelines
Until 19661967-21602161-22642265-22992300-23632364-2379Since 2380Alternate TimelinesAbramsverseDiscoverse
DS9: The Visitor (alternate timeline, analysis)
2372 In a parallel timeline, Benjamin Sisko disappears from the Defiant's engine room into subspace and is presumed dead.2373 The Bajorans agree to a mutual defense pact with the Cardassians against the Klingons. Ben Sisko appears to Jake on DS9.
2374 After five years on the station, Jake has to leave because the Federation turns over Deep Space 9 to the Klingons.
2382 Jake Sisko marries Korena.
2389 Ben Sisko appears in Jake's house.
2391 Jake Sisko begins to study subspace physics at the age of 37.
2408 Benjamin Sisko appears from subspace for the last time until 2422.
2422 Aboard the Defiant, Jake Sisko attempts to get his father back from subspace.
Around 2450 Jake Sisko dies while being visited by his father from subspace, thereby releasing the subspace tie between them and transferring Ben back to the year 2372. This timeline ceases to exist.
VOY: Future's End and Relativity (alternate timeline, analysis)
1967 Henry Starling finds the wreckage of a crashed timeship from the 29th century in the Sierra Nevada. In the following years the future technology enables a premature computer revolution (VOY: "Future's End").1996 Henry Starling launches the timeship, thereby causing the disaster that destroys the Sol System in the 29th century (VOY: "Future's End").
2371 Capt. Braxton sends Seven of Nine back to this year to investigate the ship at Utopia Planitia (VOY: "Relativity").
2372 Capt. Braxton sends Seven of Nine back to this year to investigate the ship during a Kazon attack (VOY: "Relativity").
2375 Voyager is destroyed in the blast of Capt. Braxton's bomb (VOY: "Relativity").
29th century A massive explosion destroys Earth's solar system, for which the crew of Voyager is blamed. Capt. Braxton travels back to the 24th century to eliminate Voyager, but he fails and his ship crashes on Earth in the late 20th century. It turns out that actually Henry Starling would be responsible for the disaster. Thanks to Voyager's interference in the year 1996 he can be stopped, so the explosion does not take place (VOY: "Future's End").
Some time later in the 29th century Capt. Braxton is arrested after is has been discovered that he will try to destroy Voyager (VOY: "Relativity").
Still some time later in the 29th century Capt. Braxton who spent years on 20th century Earth devises a plan to destroy Voyager (VOY: "Relativity").
VOY: Living Witness (possible future)
31st century The Kyrians blame the ruthless "warship Voyager" for causing a war with the Vaskans 700 years ago. When the backup module of Voyager's EMH is reactivated in a museum on the Kyrian homeworld, the Doctor corrects this wrong view of history that has been established throughout the centuries.Six years later in the 31st century Quarren, director of the Kyrian museum, dies, but not before he can witness the dawn of harmony on his planet.
Many years later in the 31st century The EMH, having become a renowned person on the Kyrian homeworld, finally takes a shuttle and heads for the Alpha Quadrant.
VOY: Timeless (alternate timeline, analysis)
2375 Voyager is destroyed and all of the crew are killed when the ship crashes on a planet after a failed attempt to use slipstream drive.2379 In this parallel timeline, Harry begins calculations of new slipstream data for Voyager, to prevent the ship from crashing.
Prior to 2380 Starfleet gives up the search for the missing USS Voyager.
2389 Harry Kim and Chakotay hijack the Delta Flyer and successfully prevent Voyager from crashing on a planet. This timeline ceases to exist.
VOY: Endgame (alternate timeline, analysis)
2377 Instead of entering the transwarp conduit, Voyager continues on its course to Earth through normal space in this parallel timeline.Between 2377 and 2380 Chakotay and Seven of Nine get married.
2380 After being injured on an away mission, Seven of Nine dies on Voyager.
2392 The Doctor invents a synaptic transceiver for a neural interface.
2394 Voyager returns to Earth after 23 years in the Delta Quadrant. Commander Chakotay dies in the same year.
2400 Sabrina, Naomi Wildman's daughter, is born. Captain Harry Kim departs on a four year mission of deep space exploration. Ensign Miral Paris begins working on acquiring a temporal device from the Klingons.
2404 Captain Harry Kim returns from his four year exploration mission. Voyager's EMH names himself Joe, in honor of his new wife's grandfather. Admiral Janeway travels back in time to 2377 and prevents this parallel timeline from happening.
Temporal Cold War (possible future and alternate timelines, analysis)
1916 In a parallel timeline set off by Vosk, Lenin is assassinated before he can start the Communist Revolution. Without the Soviet Union as his main enemy Hitler defeats his enemies in Europe faster than he should (ENT: "Storm Front").
1944 The Nazis have conquered the East Coast of the USA thanks to their alien allies. New York and Washington are occupied territory, major battles take place in Ohio and Virginia (ENT: "Storm Front").2154 Captain Archer is suffering from a parasite that erases his memory. T'Pol takes command of Enterprise. The Xindi weapon is detected too late, and Earth is completely destroyed (ENT: "Twilight").
2166 Captain Archer is still suffering from the parasite and is living with T'Pol and a few thousand human survivors on Ceti Alpha V. Phlox has devised a therapy to destroy the parasites, which exist outside normal space-time, using a subspace implosion in a special chamber. The device is installed on Enterprise, now commanded by Captain Tucker. But the Xindi have located the human settlement and are attacking the system. Phlox finds out that the eradicated parasites don't only vanish in the present, but also in the past. When the chamber is damaged in the attack, Archer, Phlox and T'Pol set the warp core to overload to create the ultimate subspace implosion. The ship explodes, and the past is changed. (ENT: "Twilight").
Prior to 2550 The Xindi homeworld is allegedly destroyed by the people of Earth (ENT: "The Expanse").
Around 2550 A fleet of the Federation, now encompassing the Klingons, wins the Battle of Procyon V against the Sphere Builders (ENT: "Azati Prime").2769 Anthropologists from this year watch the construction of the pyramids of Giza (ENT: "Cold Front").
28th century According to Daniels, his opponents in the "Temporal Cold War" come from this century 300 years before his time. They don't yet have the possibility to travel to the past but only project images of themselves (ENT: "Shockwave").
31st century Daniels leaves for the 22nd century to stop Silik's incursions in the "Temporal Cold War" (ENT: "Cold Front").
31st century Earth is devastated because of a different history that never saw the foundation of the Federation (ENT: "Shockwave").
Confederation Timeline (alternate timeline, analysis)
1893 Guinan does not meet Picard in San Francisco because he doesn't travel back in time (TNG: "Time's Arrow II", PIC: "Watcher").This is the only known incident in Star Trek where a time travel causes the past of the point of divergence to change as well, which seems logical but has several (complicated) implications.
2024 Renée Picard is killed or otherwise does not embark the Europa Mission. She doesn't find alien microbes that would help clean Earth's atmosphere. Earth subsequently uses Soong's methods (PIC season 2).
There is no clear indication what would have to happen to set off the alternate timeline and when in the sequence of events it does happen.
2024 Earth has become the Confederation, a xenophobic empire that has conquered the Romulans and the Borg among many other races (PIC: "Penance").
"Admiral Picard" and "President Annika Hansen" are important figures of this fascist regime. But most likely these personalities were made up by Q because the second law of thermodynamics would forbid their existence.
Other Future Timelines (possible future)
2395 In this timeline (which has been fabricated by Q), the Klingons have conquered the Romulan Empire. Picard investigates a strange phenomenon in the Neutral Zone, being a guest on Beverly Picard's starship Pasteur. The Pasteur is destroyed by the Klingons, but its crew is rescued by the USS Enterprise NCC-1701-D (TNG: "All Good Things").Early 25th century Alexander possibly becomes a peacemaker, tragically causing Worf's death in the Klingon High Council (TNG: "Firstborn").
26th century A researcher from this time travels back to the 22nd century where his time pod is stolen by Berlinghoff Rasmussen (TNG: "A Matter of Time").
27th century Scientist Kal Dano invents the Tox Uthat, a quantum phase inhibitor. Two Vorgon criminals attempt to steal the device hidden on Risa in the 24th century, but Enterprise-D captain Picard orders it destroyed (TNG: "Captain's Holiday").
See Also
Time Travel - General Considerations - six theories on how time travel may "work" logically, and other musings