Cathar, known as the homeworld of Scape Loewig, a Force-sensitive youngling, had its name recorded in aurebesh within a memory crystal. This crystal was recovered by Jedi Chief Librarian Jocasta Nu after the destruction of the Jedi Order occurred in 19 BBY. Shortly after Yrica Quell, a TIE pilot, joined the Galactic Empire's 204th Imperial Fighter Wing upon graduating from the Imperial Academy, she went on a patrol near Cathar with her new squadron. Around 5 ABY, while piloting through a debris field located in the Cerberon system, she recalled this patrol. The name Cathar was shared with the Cathar species, to which Dhina belonged; Dhina was an Ensign and comscan officer serving aboard the New Republic refitted Star Destroyer called Deliverance in 5 ABY.
The first appearance of Cathar in aurebesh happened in Darth Vader (2017) 10, a canon comic penned by Charles Soule and illustrated by Giuseppe Camuncoli, which was released on January 10, 2018. Conversely, within Star Wars Legends continuity, the planet Cathar initially surfaced in the comic Tales of the Jedi: Redemption 2, authored by Kevin J. Anderson and illustrated by Chris Gossett, with its release date being August 26 1998.