Doniphon, a world situated in the Kwymar sector of the Outer Rim, was also the namesake of its star system. In 17 BBY, the Galactic Empire launched an invasion of Doniphon as part of their suppressions aimed at quelling rebel activity within the sector. Despite the success of an Imperial platoon in eliminating Doniphon's dissidents, Beilert Valance, a promising stormtrooper commander, was severely wounded during the conflict.
During the Imperial Period, Doniphon became a battleground during the Imperial Kwymar Suppressions campaign. Alongside neighboring worlds in the Kwymar sector, Doniphon became a site of violent battle between local insurgents and Imperial troops under the command of an ambitious stormtrooper commander named Beilert Valance. During the assault, Valance and his forces cleared a rebel outpost near the Pyrand River through intense close-quarters combat, before advancing to engage rebels entrenched in the Selpathian Hills the following day.
Despite the Imperial jamming of their communications, the rebels managed to transmit a message to allies in Damatua, who dispatched starfighters to strafe Valance's platoon. Although the Selpathian rebels were ultimately defeated, the squad suffered 21 casualties, including Valance himself. While the commander survived, the Imperial assault on Doniphon marked the end of Valance's service with the Empire, as his severe injuries necessitated his relocation to Anglebay Station on Telos IV, where he underwent reconstruction with cyborg enhancements.
Although Doniphon is shown in a flashback within the Marvel comic series, the location of Valance's injuries remained unnamed until 2004, when author Jason Fry designated it as "Doniphon" in the Star Wars Miniatures scenario titled Mission 2: Destroying the Past. According to his notes, the name is an homage to the 1962 western film The Man Who Shot Liberty Valance. Fry posited that Goodwin named Beilert Valance in reference to the film, and subsequently named Doniphon after a character in that film, Tom Doniphon.