Thrawn was a blue-Skinned Chiss who served as a Grand Admiral in the Empire, but was sent off on some mission and appeared in no movies. This really annoyed Thrawn who desperately wanted to be famous. He was always showing up just after a movie-worthy event occurred. During the Battle of Endor he was filming a reality TV series about being an Imperial Grand Admiral. Unfortunately, after the battle, the show was canceled before a single episode was shown. Thrawn was enraged and demanded to speak to the Emperor himself. When he found out his Empire was done with, and went after Luke Skywalker before being defeated. I think that's what happened, but I've never read those books. Screw the EU.