Quentin Tarantino originally went to Will Smith to play Django in Django Unchained, and that would have been a brilliant bit of casting. The globe's most beloved, safest black superstar shooting a white lady in cold blood? Amazing!
But Smith passed on the part, and now he has given Entertainment Weekly his official reasoning. I almost buy this:
Django wasn’t the lead, so it was like, I need to be the lead. The other character was the lead! I was like, ‘No, Quentin, please, I need to kill the bad guy!
It's interesting to hear a big Hollywood star be open about something like that - he has to be the top guy in the movie, he can't share the spotlight. Of course that's an enormous misreading of Django Unchained on every level, but I also believe that Smith sort of simply didn't get the script.
I think there's more behind Smith's passing on the part, including the fact that he was uncomfortable with some of the film's racial aspects and that he wanted to have a rewrite done, but that goofy quote does seem to sum up enough of it.