It is referenced that masters would rape their female slaves. This is never shown or discussed.

About a 20 second scene of a woman giving birth. (Not explicit and no direct nudity shown. Lady screams in birth pains)

There is a closeup of someone being shot. We see some blood on the clothing.

A man's head is shown off from a canon. This happens so fast that you have to pause the movie to actually see any details.

Civil war era medical triage, including: crude amputations, gaping wounds, bloody dressings and so on.

Members of the klan burn a black church to the ground; Members of the klan dragging a black man out of his house and beating him and then shooting him.

Intense war scenes.