Boss' numerical designation is RC-01/138, or RC-1138. This is likely a reference to one of George Lucas' very first feature films, the critically acclaimed "THX 1138."

A sequel to Star Wars: Republic Commando was planned, titled Imperial Commando, which focused around the Imperial Commando Units who were the elite ground combat troops of the Galactic Empire. The sequel was already planned before the game's release in 2005, but was canceled in 2004, only reaching the concept stage.

The fundamental design of the player's view always being in the helmet was based-off of Metroid Prime, which the developers loved.

The reason why the opening Clone facility cut-scene was not skippable is due to technical concerns from the game's Lead Programmer, Brett Douville. Due to the data that needed to be installed onto the original Xbox hard drive to allow the game to perform efficiently, on initial release Xbox consoles this process would've taken more than 50 seconds. The unskippable cut-scene would allow the assets to stream while the player sees it and allow it to install them in time regardless of the console model.

The idea to make it easily skippable in the PC version was late in development so the concept wasn't put in for that release.