The USS Endeavour (NCC-71805) was a Federation starship that was in service to Starfleet in the latter half of the 24th century.
In 2368 the Endeavour was assigned to the Starfleet blockade force at the Klingon-Romulan border during the Klingon Civil War. It was the last ship to clear the drydock prior to the departure of the fleet from Starbase 234. During the initial deployment of the tachyon detection grid, the Endeavour was linked with the USS Ajax, USS Hood, USS Tian An Men and USS Enterprise-D. (TNG: "Redemption II") Later that year, the ship was assigned to a patrol circuit in the Cleon system. (TNG: "The Game")
Captain Amasov of the Endeavour was at some point involved in a conflict with the Borg sometime prior to 2371. After the encounter, Amasov reflected, "...It is my opinion that the Borg are as close to pure Evil as any race we've ever encountered." (VOY: "Scorpion") In 2373, the Endeavour again faced the Borg at the Battle of Sector 001. (Star Trek: First Contact)