Star Wars: Knights of the Old Republic (KotOR) is a role-playing video game developed by BioWare and published by LucasArts. It was released for Microsoft's Xbox on July 15, 2003, for PCs running Microsoft Windows on November 19, 2003, and later for Mac OS X . KotOR is the first computer role-playing game set in the Star Wars universe. The sequel, Star Wars: Knights of the Old Republic II: The Sith Lords, was developed by Obsidian Entertainment at BioWare's suggestion as BioWare wanted to focus on their own intellectual properties.