6/28) This was the first movie in over 16 years where Leonardo DiCaprio did not get top billing.
7/28) Quentin Tarantino stated that originally the mandingo fight scene and the scene with the dogs were longer and more violent, and that he had to cut it down because he didn't want to 'traumatize' the audience.
8/28) This was Leonardo DiCaprio's first role as a villain since The Man in the Iron Mask. He was uncomfortable with how horrible and explicitly racist his character was. Tarantino assured him that he had to be as mean and horrible as possible, and said people would hold it against him forever if he didn't take it all the way.
9/28) Despite their high-billing, Leonardo DiCaprio does not appear until 63 minutes into the movie, while Samuel L. Jackson doesn't appear until 86 minutes into the movie.
10/28) After an accident in training where Christoph Waltz was thrown off his horse and broke his pelvis, Jamie Foxx gave him a gift to make him feel better about riding a horse: a saddle with a seat belt.