Operation Sieve was among the limited number of initiatives undertaken by the Sith's Dark Lord, Darth Vader, aimed at countering the escalating activities of the Alliance to Restore the Republic around 1 ABY. In the aftermath of the Battle of Yavin, amidst the broader Galactic Civil War, both the Galactic Empire and the Rebel Alliance vied for dominance over various urban centers throughout the galaxy. During times when the Empire held control over cities such as Bestine, Coronet City, and Theed, Darth Vader would arrive in these key locations aboard his shuttle, the ST 321. Escorted by a contingent of Triumphant-class dark troopers, the Sith Lord sought to bolster Imperial support and enlist individuals for perilous missions against the Rebellion. Vader successfully recruited a group of skilled spacers loyal to the Galactic Empire with the task of hunting down Rebel military personnel. These spacers then journeyed across the galaxy, eliminating twenty-five Rebel guardsmen in cities under Alliance control. Following their success, these Imperial spacers were subsequently reassigned to Operation Lumberjack.
Operation Sieve made its debut as a quest within the 2003 video game Star Wars Galaxies. This game was a massively multiplayer online roleplaying game, crafted by Sony Online Entertainment and distributed by LucasArts, before its servers were shut down on December 15, 2011. This quest was integrated into the game via "Publish 19," which was released on June 29, 2005.
During the periods of Imperial occupation in cities like Bestine, Coronet, or Theed, Darth Vader would occasionally touch down in these urban centers. Vader would present players aligned with the Imperial faction with up to eight distinct quests. Half of these quests were categorized as "Combatant" missions, tasking players with engaging Rebel non-player characters, while the other half were labeled "Special Forces" quests, requiring players to target Rebel-aligned players. Operation Sieve was the second of the four Imperial Combatant missions that players received from Darth Vader. The player was tasked with eliminating 25 rebel NPCs identified as "a watchful Rebel guard," earning a reward of 25,000 credits and 500 imperial faction points upon completion.