Pax, a world, could be found within the Expansion Region and Trailing Sectors, specifically at coordinates N-16 on the Standard Galactic Grid. The Hydian Way, a well-known hyperspace route, provided a link between Pax and both the Chardaan system and the planet ZeHeth. Furthermore, another hyperspace lane connected it to the celestial bodies Kira and Vondarc.
Sometime around 9 ABY, the name of Pax appeared on the computer display of Kh'ymm, an astronomer, as she researched her archive of planets from the Observatory Moon. Her goal was to discover the possible location of the lost planet At Attin. Later, in 34 ABY, the [Halcyon], a Star Cruiser belonging to Chandrila Star Line, journeyed past Pax during a cruise that originated in the Chandrila system of the Core Worlds and headed towards the Outer Rim Territories. A partial map of the galaxy, showing the location of Pax, was visible on several screens within the starship.
The initial mention of Pax in current Star Wars canon occurred in the fourty-third edition of the magazine Star Wars: Build the Millennium Falcon, released around October 28, 2015. Pax's first appearance in-universe was as a location on a map within Star Wars: Galactic Starcruiser, an immersive role-playing experience at Walt Disney World Resort in Florida, which opened its doors to the public on March 1, 2022.
The Pax system was originally created for the Star Wars Legends continuity in the 1993 sourcebook Twin Stars of Kira, a supplement for Star Wars: The Roleplaying Game by West End Games. Within that book, the star system was featured in the roleplaying game adventure named "Treasure Hunt," authored by Todd Quigley and featuring illustrations by Tim Eldred.