Gap Nine was a remote, insignificant planet characterized by swamps, and was the homeworld of an unidentified reptilian species.
The Galactic Republic achieved a victory over a Sith invasion force at Gap Nine in 1500 BBY, amidst the New Sith Wars.
Centuries prior to the Galactic Empire's ascendance, a group constructed temples dedicated to dark spirits on this planet. These individuals were later defeated by the Jedi, who subsequently converted the temples into repositories of information.
As the years of the Galactic Empire unfolded, these temples became targets for looting, with their valuable artifacts stolen, and an Imperial fuel-ore processing plant was constructed on the world.