USS Excalibur (NCC-26517)

The USS Excalibur (NCC-26517) was an Ambassador class Federation starship in service in the 24th century.

History
In 2333, the Excalibur was under the command of Captain Shastakovich and was part of the task force organized to fight an unknown vessel attacking Federation vessels. (Stargazer novel: Enigma)

The vessel was captained for several years by Captain Morgen, the heridatary ruler of the planet Daa'V, until Morgen returned home in early 2367 to assume the planetary throne after the death of his father. (TNG novel: Reunion)

In early 2368, while the vessel was "in between" captains, Commander William T. Riker briefly commanded the ship during the brief Klingon civil war. Lieutenant Commander Geordi LaForge served as Riker's first officer. (TNG Redemption).

Following the Klingon civil war, command of the Excalibur was given to Captain Morgan Korsmo, following the destruction of his previous vessel, the USS Chekov, by the Borg in late 2367. Lieutenant Commander Elizabeth Shelby, following Korsmo from the Chekov, was assigned to the Excalibur as First officer. (TNG novel: Vendetta; Tales from the Captain's Table: Pain Management).
 * (The computer game Starship Creator: Warp depicts Korsmo in command of the Excalibur as early as 2362. This is in contradiction with Korsmo's command of the Chekov''.)

In 2369, the Excalibur stopped at Starbase Deep Space 9 before embarking on a diplomatic mission to Vigan Delta V. Later that year, the Excalibur encountered Borg Cube 45208 and a number of Excalibur personnel were assimilated, including Lieutenant Marika Willkarah, who had served on Excalibur for just over a year. (VOY: Distant Shores: Brief Candle; DS9: Stowaways short story, "Making a Difference" No Limits)).

In 2371, the Excalibur went to Lintar IV to rescue Worf, William T. Riker, Deanna Troi, and Alexander Rozhenko from the Romulan Sela, who had held them prisoner. (TNG novel: Imzadi II).

Later that year, the Excalibur went to Argelius II to pick up Burgoyne 172, the ship's new assistant Chief Engineer. (No Limits: "Through the Looking Glass").

Captain Korsmo was killed in battle against the Borg on stardate 50391.5, in the year 2373. His last order to Commander Shelby was to see to the safety of all hands. (''"Making a Difference")

Alternate timelines
In the Pendragon timeline, following Captain Korsmo's death in the Battle of Sector 001, Elizabeth Shelby was promoted to Captain and given command of the Excalibur. Captain Shelby followed her former commanding officer's lead and supported Admiral James Leyton during the Federation Civil War.

The Excalibur was destroyed during Operation Return in early 2374. (Star Trek: Pendragon)