Until 0 ABY, the Relentless was commanded by Captain Parlan, who directed the Imperial search for Adar Tallon on Tatooine. After failing in his mission, Parlan was executed by Darth Vader. Soon afterwards, Captain Westen was given command of the Relentless, but he met the same fate when he, too, failed Lord Vader.
By 4 ABY, Captain Dorja was in command of the Relentless. A cautious commander, Dorja commanded the vessel during the Battle of Endor, where the Relentless was distinguished by not sustaining any casualties. Afterwards, the Relentless retreated along with the Chimaera, and remained part of the fleet faction which Thrawn would eventually command. Dorja's personal differences with the Chimaeras captain, Gilad Pellaeon, and Grand Admiral Thrawn relegated him to a minor role in the latter's campaign of 9 ABY. The Relentless played a role in the Raid on New Cov, where its crew attempted to capture Han Solo and Luke Skywalker. The Relentless also saw action during the capture of the Ukio system and the Battle of Bilbringi.
The Relentless, still under Dorja's command, eventually entered the service of the Imperial Remnant's Braxant Sector Fleet, taking orders from Moff Vilim Disra and Pellaeon (now a Fleet Admiral). In 19 ABY, the Relentless was sent by Disra to intercept a Corellian corvette near Morishim. This corvette carried Colonel Meizh Vermel, a courier sent by Pellaeon to enter peace negotiations with the New Republic. Later that year, the Relentless was at the Battle of Yaga Minor, carrying the Remnant's ruling triumvirate (Moff Disra, Major Grodin Tierce, and the Thrawn impersonator Flim).
In 28 ABY, following the Imperial Starfleet's retreat from the Battle of Bastion and the withdrawal at Yaga Minor, the Relentless led Fleet Group Relentless, one of four temporary battlegroups created for the defense of Borosk against the Yuuzhan Vong invaders. Following the battle, the Relentless was among the Star Destroyers ordered deployed from Borosk to assist in the defense of Yaga Minor. Following Yaga Minor, the Relentless accompanied the Right to Rule on its hunt of the remaining forces of B'shith Vorrik to Generis and then Esfandia where it participated in the Battle of Esfandia.
- The Star Wars Rules Companion
- Dark Force Rising Sourcebook
- The Thrawn Trilogy Sourcebook
- Star Wars Encyclopedia
- The Complete Star Wars Encyclopedia
- The Essential Guide to Warfare
- Star Wars: Armada — Imperial-class Star Destroyer Expansion Pack