But that all changed today with the release of the new Star Wars Rebels season 3 trailer, which premiered at the Star Wars Rebels panel during Star Wars Celebration.
But more important than his involvement in the Rebels animated series specifically is the fact that the character is now an official part of the new Disney Star Wars canon.
The character of Thrawn is a major villain in Star Wars history.
As many fans know, when Disney purchased Lucasfilm, the official canon of the Star Wars movie universe became a bit tricky.