Did you know that George Lucas originally wanted Luke Skywalker to become Darth Vader at the end of Return of the Jedi? His last lines were going to be "Now I am Vader. Now I will go and kill the [Rebel] fleet and I will rule the universe." That would have been cool. It's one of ten unknown facts about the movie.
A movie that sadly became an ad for stupid Ewok merchandise instead of its original dark vision: Wookie guerrillas fighting the Empire in their home planet, while other Wookies were enslaved to build the second Death Star and the Rebels tried to take over the Empire in an epic final battle. That's what Lucas first envisioned: a Vietnam-style war movie. But he gave us bloody teddy bears.