(covers information from an alternate timeline)
This page contains information regarding Star Trek: Discovery, and thus may contain spoilers.
The Temporal War began when a rogue time-traveling faction, the Na'kuhl, returned to the 29th century after making several changes to Earth's history. With this egregious violation of the Temporal Accord, all the time-traveling factions began attempting to wipe out the others from existence. As a result, an already-existing Cold War escalated into a full-scale conflict.
After being defeated in the Temporal War by the last of the temporal agents, the Na'kuhl Vosk escaped through stealth time travel to the 1944 of an alternate timeline where he and his faction used 20th century technology to build a temporal conduit to return to their own time. Once in their own time, the Na'kuhl defeated most of the temporal agents and the Temporal Cold War turned into a full Temporal War with each faction causing dozens of changes throughout the timeline in an attempt to wipe each other out.
In a desperate attempt to avert the Temporal War, the temporal agent known as Daniels transported Enterprise NX-01 and Captain Jonathan Archer from the end of the Xindi incident to 1944 of a Na'kuhl-altered World War II. Daniels hoped that by stopping Vosk from returning to his own time period, the Temporal War would be averted and the timeline restored to normal. The Cabal's mysterious benefactor also dispatched Silik to stop Vosk and gain the plans for the temporal conduit so he could use the technology for himself and his own faction.
After arriving in 1944, Enterprise and her crew learned of the altered timeline and Vosk's presence. Before dying, Daniels informed them of the events leading up to the Temporal War and the need to kill Vosk to prevent it. As Vosk's compound was equipped with shields, Archer decides to enlist the aid of Silik to enter the compound and lower the shields so that Enterprise could bomb it and destroy the temporal conduit. With the help of Alicia Travers, Archer was able to enlist the aid of the American Resistance to attack the compound as a distraction. As the Enterprise was damaged by Vosk's plasma cannon, it needed to get close enough to bomb the compound directly using visual scanners. (ENT: "Storm Front", "Storm Front, Part II")
Battle over New York
Under the command of Carmine, a group of American Resistance Fighters assaulted the entrance to Vosk's compound, killing several Nazi soldiers. As the resistance fighters began to be outgunned, Alicia arrived with more fighters. The Na'kuhl detected the development but Vosk saw it as a fortuitous development, telling Kraul that the Nazis would be too distracted dealing with the resistance fighters to interrupt their preparations to return to the 29th century.
As the resistance fighters distracted the Nazis, Archer and Silik sneaked to a side door into the compound which was locked from the inside. Silik was able to use his Suliban enhancements to make his way through a vent next to the door and let Archer into the compound. Archer reported on the developments to T'Pol, who informed him that the Enterprise would have to enter the atmosphere in order to target the facility. Archer ordered her to do so once the compound's shields were down. Despite having to briefly hide from enemy forces, Archer was able to use a console and the information from Silik's data disk to lower the compound's shields. Archer and Silik were then engaged by Nazis and took them out, but not before Silik was shot and mortally wounded. Though Archer tried to signal Enterprise for a beam out, he was unable to reach them due to ionization in the atmosphere and Silik died moments later. Attempting to leave the facility, Archer encountered Trip Tucker, who had been previously trapped there by Silik. After seeing Silik's body, Tucker realized that Archer was who he said he was and they fled the compound together.
After Archer lowered the shields around the compound, T'Pol ordered the Enterprise into Earth's atmosphere. Detecting the development, Vosk ordered the plasma cannon deployed, but his men weren't able to spare the power while attempting to use the temporal conduit. Instead, Vosk ordered his squadron deployed. The Nazi Generalmajor attempted to take the squadron from Vosk, but Vosk killed him and his men and ordered his squadron deployed.
On the Enterprise, Malcolm Reed reported that targeting scanners couldn't get a lock and switched to visual scanners. T'Pol ordered the Enterprise slowed to 200 kilometers per hour as Hoshi Sato detected the launch of Vosk's squadron.
Outside the compound, Tucker and Archer emerged and Carmine had Nicky Giorgo cover their retreat. Archer warned Carmine of the impending bombing and had the resistance fighters flee. Archer promised Alicia to restore her life to normal and he and Tucker beamed back to the Enterprise.
On the Enterprise, the crew initially believed the approaching squadron to be harmless but discovered them to be equipped with plasma cannons. Archer entered and took command, ordering photonic torpedoes prepared as the Enterprise used her phase cannons to fight off the squadron.
In the compound, the Na'khul were successfully able to open the temporal conduit into the future and Vosk prepared to return to his own time. Moments before Vosk could return to the 29th century, Reed reported he had the compound targeted and Archer ordered him to fire. Closing to point-blank range, the Enterprise fired three photonic torpedoes at the compound, destroying it as Vosk entered the conduit, destroying the conduit before it could be used and killing Vosk. (ENT: "Storm Front, Part II")
Following the death of Vosk, the restored Daniels informed Archer that the Enterprise was successful; Vosk was killed before he could return to the 29th century and spark the Temporal Cold War into a full Temporal War. With Vosk's death, all of the damage to history was reversed and the correct timeline was restored. Daniels informed Archer that the battle ended the Temporal Cold War for good and returned Archer and the Enterprise to their own time. (ENT: "Storm Front, Part II")
In response to flagrant attempted misuse of its capabilities, the Guardian of Forever relocated from its original planet to Dannus V, and became more wary of would-be time travelers. (DIS: "Terra Firma, Part 2")