U.S.S. Defiant NCC-1764
Construction began on the Constitution class Starship Defiant at Tranquility Base, Luna, in 2250, and the ship was commissioned on Reference Stardate 1/9311 (November 2251).[Notes 1] During the early years of her service, the Defiant conducted many missions of importance for Starfleet, and constantly patrolled the Klingon Neutral Zone as tensions between the two powers continued to rise prior to the start of the Four Years War. On Reference Stardate 1/9407 (July 2252), the Defiant, with a squadron of Baton Rouge class cruisers, destroyed a Klingon task force that was raiding supply convoys during the Four Years War, but by Reference Stardate 1/9505 (May 2253), the Defiant and her Constitution class sister ships were redeployed away from the fighting. During the ship's early years, the Defiant became the sixth Federation starship to encounter the N'shaii, and was easily able to dispatch them. Wendell Maynard served aboard the Defiant for two years, shortly after the ship was launched.[Notes 2] On Reference Stardate 2/0303 (March 2261), the Defiant was refit to Mark III specifications.
In late 2265, the Defiant returned from her first five-year mission, and Captain Serling stepped down as commanding officer. He was replaced by Captain Thomas Blair, who took the Defiant out on her second five-year mission in early 2266. Amid increasing tensions with the Klingons, the Defiant was once again posted along the Neutral Zone. By 2267, the Defiant had been assigned to operations in the Taurus Reach. That year, it accompanied the U.S.S. Endeavour NCC-1895 and the U.S.S. Akhiel on a mission to drive Klingon forces off of Golmira, a low-tech planet where a Shedai conduit had been discovered.
On Reference Stardate 2/0910 in 2268, the Defiant was called to the Klingon colony on Traelus II after receiving a distress call. A landing party discovered no Klingon survivors left on the colony, but they recovered a land-based web generator of Tholian origin. The Defiant set a course back for Federation space, but soon found themselves being pursued by three Tholian vessels. Trying to escape the Tholians, the Defiant entered a spatial interphase and became trapped. This interphase had an adverse effect on humanoid neurophysiology and caused mass insanity among the crew. Captain Blair managed to get a distress call out to the U.S.S. Enterprise NCC-1701 before the crew succumbed to madness and started to kill each other.
By the time the Enterprise arrived at the Defiant's location on Stardate 5693.2, three weeks had passed. The crew of the Defiant was dead, and the ship had been drawn deeper into the interphase rift. Interference from the Tholians prevented the Enterprise from retrieving the Defiant, and the ship was left behind. The Defiant was last seen shimmering, suspended between dimensions, until it faded into interspace.
The interphase, however, was actually a rift between realities created by the Tholians of the Mirror Universe in 2155. The Defiant, after disappearing from its universe of origin, appeared in that universe and was taken by the Tholians to a drydock in the Vintaak system for study. Word of this eventually reached Commander Jonathan Archer, first officer of the I.S.S. Enterprise NX-01, who saw the ship as an opportunity to seize power for himself within the Terran Empire. He seized control of the Enterprise from Captain Forrest long enough to reach the Defiant. While Archer led a boarding party to the Defiant, the Enterprise was detected by the Tholians and destroyed. Using the Defiant's advanced weapons, Archer was able to rescue most of the Enterprise crew and escape back to Imperial space, where it quickly became obvious that the balance had just tipped back in favor of the Empire in an ongoing civil war, led by Vulcans and Andorians who sought to unseat the Humans in control of the Empire. The Defiant rendezvoused with an assault fleet, but discovered the I.S.S. Avenger NX-09 was the only ship remaining. Destroying the rebels, Archer then proceeded to assassinate Admiral Black, and decided he was going to use the ship from the future to overthrow the Emperor. The alien crew members on the Avenger, however, led by T'Pol and Soval—inspired by the Defiant's database, which described a United Federation of Planets in the other universe—convinced Dr. Phlox—the only remaining non-Terran aboard the Defiant—to disable the ship, allowing the Avenger to attack. However, the crew was able to restore the ship's systems and destroy the Avenger, killing Soval. Shortly after arriving at Earth, Archer was poisoned by Hoshi Sato, formerly the Captain's Woman to Forrest and an old flame of Archer's as well, who then declared herself empress.
When Starfleet refused to surrender, the Defiant engaged a fleet of seven Terran vessels, including the dreadnought I.S.S. Imperator; four NX class battlecruisers, including the I.S.S. Broadsword and I.S.S. Khan's Wrath; as well as a pair of destroyers. Despite this heavy resistance, the Defiant was able to disable the Imperator and destroy three of the NX class ships before bombarding Starfleet Headquarters from orbit, eliminating Fleet Admiral Gardner.
MACO Sergeant Travis Mayweather was appointed the ship's captain, and over the next few months the interior and exterior appearance of the Defiant was modified to reflect Empress Sato's propaganda that the ship was from the future of the Mirror Universe, where the Terran Empire flourished into the 23rd century. The Defiant was also the subject of a massive attempt to reverse-engineer its weapons systems for installation on other Terran vessels. The Defiant was sent to the Devolin system to search for a potential rebel base; this was revealed later to be a ploy by General Shran to get the powerful ship away from Earth, leaving it vulnerable to a rebel attack. The ship later participated in battle over Aldus Prime against rebel ships in an attempt to rescue Empress Sato. After her successful rescue, Sato discussed with T'Pol, now the Regent of Vulcan, about sending the Defiant into an unexplored region of space to make first contact with a race believed to inhabit the area, known as the Romulans. The Defiant also apparently set a trend in the Mirror Universe for a number of ships named Defiant.
By 2257, after more than a century in the Mirror Universe, the Defiant had seen numerous modifications by the Terran Empire. The U.S.S. Discovery NCC-1031, while briefly stranded in that reality, downloaded information about the Defiant from the Terran Empire's computer networks, as well as secured files aboard the flagship of the Terran Starfleet, the I.S.S. Charon.
Another version of the Defiant, possibly either a quantum duplicate or originating from an alternate timeline nearly identical to the Prime timeline, was found drifting near the interspace rift in 2298 by the U.S.S. Excelsior NCC-2000 and retrieved in 2375 by the U.S.S. da Vinci NCC-77623 after it was rediscovered by a passing Tholian vessel.
- FASA game materials referred to events by a FASA-specific dating standard called the "Reference Stardate." All dates taken from FASA sources in this article have been adapted from that notation into standard calendar dates, which are then adjusted for errors in the baseline dates used as reference by the FASA authors. Working with a known, dated event (e.g., the launch of the Constitution class starships), the other dates in the timeline can be adjusted accordingly. FASA sources give the launch of the Constitution class as Reference Stardate 1/8801.04, which translates to the standard caldendar date of 04 January 2188. This has been established on screen, however, as occurring in 2245. As the exact month and date remain unstated in other sources, those remain the same, but the year has been adjusted to 2245, giving a modified date of 04 January 2245. This can then also be converted into the pre-TOS stardate system established in Star Trek (2009), giving us a stardate of 2245.004.
- "The Strider Incident" notes in Maynard's service record that he served aboard the Defiant, but the inferred dates put him aboard the ship from Reference Stardate 1/90-1/92 (2247-2249), long before the ship was launched. The date reference was removed from the entry.
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