This was of course in response to Chancellor Palpatine declaring himself Emperor. Mon Mothma, who made a brief appearance in Return of the Jedi and had a bigger role in Rogue One was one of the original founders of the Alliance.Here's some facts about the Alliance that you might not have known. Think Leia but also Wedge, Bail Organa and Admiral 'It's a trap Ackbar' and of course the heroes of Rogue One, Jyn Erso, Andors, Saw and our fave, K-2SO. The Rebel Alliance was one of the key groups from which meany heroes sprang in the Star Wars saga. 10 things you might not know about the Rebel Alliance