The Zaddja system, situated in the Outer Rim Territories, housed the celestial body known as Zaddja, and it was classified as a star system. Following the Battle of Yavin, the Givin cryptographer Drusil Bephorin speculated, through analytical methods, that the Alliance to Restore the Republic's fleet could be concealed within one of three systems, including the Zaddja system, as well as the Pantora system and the Kowak system. While held by the Galactic Empire, She kept this information secret, only divulging her predictions to the Rebel operative Luke Skywalker after he rescued her from Imperial captivity. The fleet was actually situated within the Pantoran system at the time of her educated guess, not the Zaddja system.
The comic book series Star Wars: Crimson Empire, a Star Wars Legends publication penned by Randy Stradley alongside Mike Richardson and distributed between 1997 and 1998, marked the initial appearance of the Zaddja system. However, the comics did not explicitly name the system. The name was instead provided in The Essential Atlas, another Legends source that came out in 2009. The novel Heir to the Jedi, authored by Kevin Hearne and published in 2015, established the system as canonized.