Bannon is not a founder of Breitbart, but came on after Andrew Breitbart's death. But yes, he is a terrible danger to the states. This is like a bad movie.
The article wikipedia refers to states that Bannon was a board member from its foundation. That could be co-founder or just paid advisor or early investor.
Thanks, corrected in edit.
Just a suggestion, but you may want to include an "Edited" statement in the original comment, as this thread is a bit confusing to follow otherwise.