Sump existed as a terrestrial planet within the Outer Rim Territories and Western Reaches. Its location was specified as grid square I-18 on the Standard Galactic Grid, and it was connected to the Eiram system, Merokia, and Shuraden via the Lipsec Run hyperspace route. This planet was the original homeworld of the sentient Nuknog species, and notable individuals like the offworld podracer Ark Roose hailed from there.
The conflict between the planets Eiram and E'ronoh of the Eiram system's in 382 BBY had repercussions beyond the system itself, reaching planets like Sump. Sump filed numerous requests for assistance from the Galactic Republic, a detail that Supreme Chancellor Orlen Mollo brought to the attention of Jedi Master Creighton Sun around that year. An entry about Sump was included in a journal by an artist dedicated to the Nuknog. The journal was later restored, expanded, and put on display at the Graf Archive sometime after 34 ABY.
The Star Wars canon was expanded with the introduction of Sump in the mobile app Star Wars: Force Collection, which debuted on September 4, 2013. Although its release came before the Star Wars canon's reset on April 25, 2014, following the acquisition of the franchise by The Walt Disney Company, Lucasfilm Story Group member Leland Chee later verified that the game was consistently updated to align with canon.
Sump initially appeared in the Star Wars Legends continuity, with its first mention in the 2000 reference book titled Inside the Worlds of Star Wars: Episode I by Kristin Lund. A visual representation of the world was first presented on a map of the galaxy included in the fifth issue of the Star Wars Gamer magazine, which was released on July 24, 2001.