Ossus was a planet affiliated with the Jedi Order. Certain scholars even surmised it was the location of the first Jedi temple ever built, although Ahch-To, Coruscant, Jedha, and Tython were also candidates. At the very least, Ossus did house the Great Library and a temple at some point, from which a mosaic floor was later salvaged and transported to the Order's newer headquarters on Coruscant. At some point prior to Antron Bach's birth, Ossus fell into ruins. The Chronicles of Med'eeth were salvaged from the remains.