A fleet belonging to the Imperial Navy, under the command of Commodore Rae Sloane, operated in the aftermath of the destruction of the planet Alderaan. During this time, the Dark Lord of the Sith Darth Vader gave the fleet orders to locate and eliminate any surviving Alderaanian refugees from their destroyed homeworld. This mission led to the fleet's involvement in the battle at Fostar Haven.
The Imperial II-class Star Destroyer Vigilance served as the flagship of the fleet, which also included five Quasar Fire-class cruiser-carriers, nine Arquitens-class command cruisers, four Raider-class corvettes, and at a minimum, five Imperial Gozanti-class cruisers.
Subsequent to the destruction of Alderaan, Darth Vader, the Dark Lord of the Sith, charged Commodore Sloane with the task of finding any survivors of the planet's obliteration. Soon after, intelligence reports indicated that an Alderaanian refugee convoy was en route to the trading outpost located at Fostar Haven. Consequently, she deployed a first wave consisting of several sub-capital ships together with Helix Squadron. Following the defection of Captain Lindon Javes, the leader of Helix Squadron, Sloane's flagship, the Vigilance, an Imperial-class Star Destroyer, arrived bearing reinforcements; however, it was unable to prevent Rebel Alliance reinforcements from aiding the convoy in its escape. The fleet suffered losses including two Arquitens-class cruisers, one Quasar Fire-class carrier, and a Raider-class corvette, in addition to various starfighters of the TIE fighter series.