Timeline: February 2154 - May 2161

TREKCORE > TIMELINE > Enterprise Season 4 (February 2154 - May 2161)

The following are events from the fourth Season of Star Trek: Enterprise

c. February 20, 2154 The Enterprise returns to Earth from Xindi space but is intercepted by Daniels and sent back in time to Earth in the summer of 1944. ("Zero Hour")

Events of "Storm Front"

Having mysteriously survived the destruction of the Xindi super weapon, a battered Archer awakes to find himself back on Earth in the 1940s in the custody of Nazi SS agents, and learns that Nazi-uniformed aliens have successfully helped Germany invade the United States. When he manages to break free of his captors, Archer joins forces with American resistance fighters to unravel the conspiracy behind the occupation.

Meanwhile, believing Archer sacrificed himself to save Earth, T'Pol and the battle-weary Enterprise crew attempt to figure out how to return to their own time. But then a near-dead Daniels appears and informs them that the future has been wiped out by a faction of the Temporal Cold War, the same faction responsible for the altered events on Earth, and they must be stopped.

Events of "Storm Front, Part II"
Archer reunites with his astonished Enterprise crew and learns from Daniels on his deathbed that a radical Temporal Cold War faction threatens to obliterate the timeline. Archer returns to the Nazi-occupied eastern United States of the 1940s, and enlists the help of resistance fighters Alicia Travers and Carmine to destroy a massive time machine under construction on the surface.

Meanwhile, hoping to forge an alliance with Archer, alien leader Vosk releases his captured prisoners Tucker and Mayweather, but this forces temporal agent Silik to emerge from the shadows to pursue his own agenda against Vosk.

(Note, most of the events of the above two episodes actually occur in the summer of 1944 in an alternate history.)
     
c. February 20, 2154 The Temporal Cold War having been prevented, Daniels returns the Enterprise to Earth in February 2154.

 
     
c. March 2154 Alternate Timeline: In the "Twilight" alternate timeline, where Archer loses his long term memory, the crew of the Enterprise finally determines where the Xindi weapon is being assembled. ("several months" after Archer is injured in "Twilight.") The Xindi intercept Enterprise, and in the ensuing battle 13 Enterprise crew are killed, and the ship's warp propulsion is crippled. Enterprise can now only achieve Warp 1.7. They eventually reach the place where the Xindi weapon was built, only to discover it has already been deployed.
     
April 2154 Events of "Home"

As the Enterprise crew revels in a heroes' welcome on Earth, Trip joins T'Pol on a trip to planet Vulcan, excited to visit her home and be introduced to her mother T'Les. But when T'Pol becomes obliged to reconsider marriage to former fiancé Koss, the future of their relationship is put in question. Meanwhile, Archer must defend some of his morally questionable decisions during the Xindi conflict before a Starfleet Command panel of inquiry. Later, Phlox experiences prejudice against aliens while taking shore leave on Earth with Malcolm and Travis.  (End of the episode is at least two weeks before the events of "Borderland")
     
May 15 - May 20, 2154 Events of "Borderland"

After a dangerous group of genetically engineered humans called "Augments" escapes from their secluded planet intent on causing all-out war between Earth and the Klingons, the Enterprise crew is called into action and Archer enlists the help of criminal genius Dr. Arik Soong, the scientist responsible for creating the Augments.

While searching for the Augments in the Borderland — the volatile region between the Klingon Empire and the Orion Syndicate — Enterprise crosses paths with a band of ruthless Orion slave traders, who kidnap T'Pol and eight other crew members off the ship so they can be sold at auction, forcing Archer to enact a risky rescue mission with Dr. Soong's help. (Date of May 17, 2154 was given in the episode)
     
May 20 - May 23, 2154 Events of "Cold Station 12"

Reunited with his genetically engineered creations called Augments, criminal scientist Dr. Arik Soong and his "children" break into the medical outpost where Soong once worked, to steal the embryos of hundreds more potential Augments with plans to build a superhuman army. They will go so far as to release the deadly pathogens stored at the facility, Cold Station 12, if the staff, headed by Dr. Jeremy Lucas, dares impede Soong's plan. Meanwhile, Archer and his crew search for clues to Dr. Soong's whereabouts on Trialas IV, the planet where he raised the Augments, leading them to find one of the doctor's less perfect children who was abandoned by his siblings. (Date is speculation)
     
May 23 - May 27, 2154
 		 Events of "The Augments"

Enterprise pursues Arik Soong and his Augments across hostile Klingon space toward a planet where the geneticist intends to go back into isolation and raise an army of genetically engineered superhumans. But Soong's "children" revolt against him and plan a biological attack upon a Klingon colony, in order to incite retaliation against Earth. (Date of May 27, 2154 is given at the end of the episode)
     
Late May 2154 Having recovered Augment DNA from the wreckage of the Bird of Prey, the Klingons begin a secret project to create genetically enhanced warriors. (Affliction)

Also, in late May 2154, the USS Columbia was originally supposed to have been launched (six months prior to Affliction)
     
June 2154 Events of "The Forge"

The Earth embassy on Vulcan is bombed, killing 31 humans and 12 Vulcans. Enterprise is called to the planet to help investigate, but the Vulcan High Command already suspects a dissident religious faction known as "Syrrannites." T'Pol learns from her husband Koss that her mother T'Les has been forced into hiding to avoid arrest — because she is a Syrrannite. Koss also brings her a mysterious heirloom containing a map. Believing this is a message from T'Les, T'Pol and Archer set out to follow that map across a treacherous desert, without the High Command's knowledge. (Date is speculation)

Events of "Awakening"

On a quest to learn the truth behind the bombing of the Earth embassy on Vulcan, Archer and T'Pol track down the Syrrannites, a revolutionary faction hiding in a desert sanctuary which includes T'Pau — the prime suspect in the bombing — and T'Pol's mother T'Les. The rebels are on the verge of being crushed by Vulcan High Command leader V'Las, but they are stunned to learn that Archer might hold the key to their survival.

While Vulcan's state of unrest grows more violent, former Ambassador Soval reveals to Trip that the High Command also plans to launch a massive sneak attack against rival planet Andoria, an act that could pull Earth into interplanetary war.  (Date is speculation)

Events of "Kir'Shara"

Archer, T'Pol and rebel leader T'Pau struggle to reach the Vulcan capital to publicly unveil their discovery of a revered ancient artifact that could revolutionize Vulcan society and topple the corrupt government.

Meanwhile, with help from allies among the Vulcans and Andorians, the Enterprise crew attempts to stop V'Las and the Vulcan High Command from launching a sneak attack upon rival planet Andoria. (Date is speculation)
     
July 2154 Events of "Daedalus"

The crew welcomes aboard Emory Erickson, the inventor of the transporter device, set to conduct a series of experiments to test a radical upgrade to the technology. However, once Enterprise reaches the test site, Archer realizes that his old family friend has lied and is using the ship to search for his son, lost years before in a transporter mishap.  (One week after the death of T'Pol's mother in Kir'Shara)
     
August 2154 Events of "Observer Effect"

After Hoshi and Trip contract a deadly virus while exploring a planet, two ghostly aliens possess the bodies of various Enterprise crew members to observe humanity's reaction to imminent tragedy. As the aliens secretly jump bodies to observe, Phlox strives to cure the stricken pair, but with his efforts failing, Archer must make a difficult decision in order to shield the rest of the crew from this growing biohazard. (Date is speculation)

In the alternate timeline, where Archer loses his long term memory, the Enterprise races back to Earth, her warp engines finally repaired (Tucker said it would take "six months" to repair the engines). The crew arrives in the Solar System not long before the Xindi weapon arrives. The Earth, in this timeline, is completely destroyed with a total loss of life. The Lunar colony is presumably destroyed at this time as well. ("Twilight")

At one point, this was when the NX-02, the second Warp 5 starship, is to have been launched from orbit around Earth. (14 months after the Enterprise is refit "The Expanse"). 
     
November 12 - 14, 2154 Events of "Babel One"

Ordered to transport a delegation of argumentative Tellarites to a peace conference with the blue-skinned Andorians, Archer and the crew find themselves drawn into a confusing, dangerous situation when a secret Romulan vessel begins attacking ships on all sides, including Enterprise. (Date of November 12, 2154 given in episode)
     
November 14 - 17, 2154 Events of "United"

Trapped aboard a mysterious drone ship that's been terrorizing the region, Trip and Malcolm work to outwit the Romulans, who are piloting the vessel via remote control, in order to save their own lives and stop the feuding Andorians and Tellarites from going to war.  (Episode takes place over a three day period, immediately after Babel One)
     
November 17 - November 22, 2154 Events of "The Aenar"

Archer visits Shran's icy homeworld to find an Andorian subspecies called the Aenar, to determine their connection to the marauder destroying ships in the region. (Dates are speculative based on prior episodes)
     
c. November 26, 2154 Enterprise returns to Earth for the launching of the USS Columbia. ("Affliction")
     
November 27 - November 30, 2154 Events of "Affliction"

On Earth, Dr. Phlox is kidnapped by a band of Klingons who are desperate to find a cure for a genetically-engineered virus that threatens their entire race. Meanwhile, Trip begins his new assignment aboard the Starship Columbia as it prepares to embark on its maiden voyage. 

(Date of November 27, 2154 is given in episode)
     
November 30 - December 2, 2154 Events of "Divergence"

With the help of Captain Hernandez, Trip and the newly-launched starship Columbia, Archer pursues the kidnapped Phlox deep into Klingon territory, as Phlox decides to cooperate with finding a cure to a virus ravaging a Klingon outpost.

Meanwhile, Archer demands that Reed disclose his secret orders when his ties to a mysterious intelligence organization are revealed. Later, when Trip temporarily returns to Enterprise, T'Pol tries to broach an uncomfortable subject with him. (Date is conjecture based on date of prior episode)
     
Early December 2154 The Mirror Universe Tholians conduct their interspace experiment, and the effect captures the USS Defiant from the "normal" universe in August 2268. The crew of the Defiant is driven mad by the effect, and driven to murder, which results in the death of the entire crew. An attempt to recover the vessel by the Enterprise in 2268 fails, and the Defiant ultimately comes through the interspace effect intact and into the hands of the Mirror Tholians who use humanoid slaves to begin looting it. (Date is speculation based on "In a Mirror Darkly, Part One", other details from "The Tholian Web")
     
December 27 - December 29, 2154
 		 Events of "Bound"

After Archer forges a deal with the Orions, the trader presents the captain with a gift -- three alluring Orion women who proceed to seduce all the men on board except, mysteriously, Trip.

(date of December 27, 2154 is given at the start of episode. Events covered two or three days.)
     
January 13 - January 17, 2155 Events of "In a Mirror, Darkly - Part One"

Note this episode takes place entirely in the Mirror Universe.

In an alternate universe, an amoral, imperialistic version of the Enterprise crew, led by Captain Forrest with Archer as his treacherous first officer, makes an astonishing discovery during a mission into enemy alien territory.

While a power-hungry Archer schemes against Captain Forrest, his lover Hoshi, and loyal slave T'Pol, so he can lay full claim to the discovery. Later, Phlox happily tortures a captured Tholian for information requested by Archer. (date of January 13, 2155 is given during episode)
     
January 17 - January 20, 2155 Events of "In a Mirror, Darkly - Part Two"
After using the Defiant to repel a Tholian attack, the power-hungry Archer and Enterprise crew set about using this advanced ship to seize control of all of Earth's Terran Empire. As Archer takes full command of the Defiant and reviews the alternate history of Starfleet, his duplicitous lover Hoshi, a traitorous T'Pol and a reptilian Gorn stowaway hatch schemes of their own.  (Date of January 18, 2155 is given during episode. Note this episode takes place entirely in the Mirror Universe)
     
January 18 - January 25, 2155 Events of "Demons" 

On Earth for a historic Starfleet conference to ratify the coalition of planets, Archer and the crew uncover a plot by a radical xenophobic group of humans called Terra Prime, led by Paxton, who want to put an end to the increasing number and influence of aliens on Earth. Meanwhile, although T?Pol contends she has never been pregnant, she and Trip learn that Terra Prime has information about their child. Later, a female reporter from Travis' past pursues him for a story. (Date of January 19, 2155 is given in the episode)

Events of "Terra Prime"

In the first steps towards the foundation of the Federation, Captain Archer and the crew must stop Paxton, a well-armed, radical human isolationist leader, who is threatening to destroy Starfleet Command unless all aliens leave Earth immediately.
     
Early 2155 In the alternate timeline, where Earth has been destroyed, the Xindi scour the Solar System and the nearby parts of the galaxy destroying all the human colonies they can find. Mars, Alpha Centauri and the Vega Colony are all destroyed. ("Twilight")
     
c. December 2155 Alternate Timeline: The surviving humans, traveling in small slow moving convoys, head out to rendezvous at Ceti Alpha V. The journey takes a year. (date is speculation from "Twilight")
     
2156 First starbase is established near the Berengeria System (speculation based on "Bound" (ENT) 

The Romulan Wars begin between Earth forces and the Romulan Star Empire. (speculation from "Balance of Terror" - noted in Star Trek Chronology)

The Romulan vessels are easy to identify by the bright markings on their hull, which are designed to look like birds. (Star Trek Chronology, "Balance of Terror" (TOS)

Also this year, two women are killed in Heliopolis City on Alpha Eridani II by an entity variously known as "Jack the Ripper" and "Redjac" ("Wolf in the Fold" - TOS).
     
c. December 2156  - In the alternate timeline where the Earth was destroyed by the Xindi, the Enterprise and her convoy arrive at Ceti Alpha V. They are the only convoy to arrive, and the total human survivor population is now very small. T'Pol resigns her commission and Tucker assumes command of the Enterprise. ("Twilight" - 9 years later, the total survivor population numbers 6,000)
     
2159 A third spaceship disappears in the Taurean region of space, never to be heard from again. ("Lorelei Signal" - TAS)
     
2160 The Romulan Wars are ended at the Battle of Cheron. The Romulan Neutral Zone is established. (Star Trek Chronology, "The Defector" TNG)
     
May 5 - 8, 2161 The events depicted in the Enterprise-D holodeck in "These Are the Voyages.." takes place:

Six years in the future, an emotional Captain Archer and the crew return to Earth to face the decommission of Enterprise and signing of the Federation charter, ratifying the newly-formed alliance of planets they helped forge.  (Episode takes place over the three days prior to the signing of the Federation Charter)
     
May 8, 2161 The United Federation of Planets is formed. ("The Outcast" (TNG), Star Trek Chronology)

The Federation is governed by a Council, located in San Francisco on Earth. 

The Federation Council President's office is located in Paris. 

Initial member worlds are Earth, Vulcan, Tellar, Andor, and Alpha Centauri. ("Zero Hour")

The founding ceremonies are held on Earth. Jonathan Archer is in attendance, and reads an important speech. (Archer visits this event with Daniels in "Zero Hour", and again is there in "These are the Voyages..") 

The entire Sol system is a founding member as Earth brings both Luna and Mars into the Federation with it as it joins. Presumably, other earth settlements such as Vega Colony are not self-sufficient enough to yet seek membership independent of Earth. (Star Trek Star Charts.) 

Section 31, which was formed at the creation of Earth's Starfleet ("Divergence"), at this time grows to become a covert organization within Federation Starfleet intelligence which deals with threats to the security of the UFP. Members of this organization defy the principles of the Federation in order to protect them, which is one of the reasons why Section 31 is not officially sanctioned by Starfleet or the Federation and its very existence is not acknowledged openly. ("Inquisition," "Inter Arma Enim Silent Leges")

Part of the Federation Charter is the non-interference directive, or Prime Directive, which prohibits interference in the affairs of sovereign planets or societies. ("Inter Arma Enim Silent Leges")