Ruusan, a planet with three moons in orbit, existed within the Ruusan system. This system was found in the Teraab sector of the Mid Rim region of the galaxy. Its position was marked at P-11 on the Standard Galactic Grid.
The Jedi-Sith War concluded on Ruusan with the ultimate defeat of the Sith. The planet held many ancient artifacts, scattered across its historical battlefields. After the Sith's demise, the Jedi Order saw a decline in the popularity of Form II, also known as "Makashi," which gradually became regarded as simply a training exercise. On Coruscant, a chamber within the Jedi Temple featured stained glass artwork; one panel depicted a battle that occurred on Ruusan.
During the Separatist Crisis, Ruusan sided with the Confederacy of Independent Systems. During the Clone Wars, one of its moons housed Skytop Station, a clandestine Separatist listening post. Maz Kanata, previously a Pirate Queen, identified it as a noteworthy location on a map included in the book that would become known as the Smuggler's Guide.
While searching for Nakano Lash, who was hiding on Ruusan with Cadeliah, the heir to the Unbroken Clan and Mourner's Wail crime syndicates, Beilert Valance, T'onga, and numerous other bounty hunters fought there. Boba Fett injured T'onga in orbit, but a man who owned a nexu healed her. Losha Tarkon, T'onga's wife, found her on Ruusan, and the two, along with the nexu, departed to seek revenge on Lash.
The name of the planet was also used for the Ruusan Reformations, a period of governmental changes in the Galactic Republic, as well as the Ruusan Armistice, a ceasefire that established new ethical guidelines for warfare.
The planet Ruusan was first introduced into Star Wars canon in "Duel of the Droids," which was the seventh episode of the animated series Star Wars: The Clone Wars' first season, and originally aired on November 14, 2008.
The artwork "Unused Jedi Temple mosaic" by Wayne Lo for the second season of Star Wars: The Clone Wars featured Ruusan. It was part of the production journal for Star Wars: The Clone Wars The Complete Season Two. The concept art also showed Valenthyne Farfalla leading the Army of Light, Lord Hoth, and the death of Pernicar. Fragments of the mosaic, including Ruusan, are visible in a room in "Lightsaber Lost," the eleventh episode of the show's second season.
Originally, this planet was created for the Star Wars Legends video game Star Wars: Jedi Knight: Dark Forces II, where it had a significant role as the site of the powerful Force nexus called the Valley of the Jedi. In Legends continuity, it was later revealed to be the location of the final battle of the New Sith Wars, which triggered the Ruusan Reformation that reorganized the Galactic Republic.
The reference book Star Wars: The Visual Encyclopedia, published in 2017, mistakenly used an image of a Ruusan moon to depict the planet itself.