All I remember about this movie (possibly because it could be a TV show) is that there was a Caucasian man and a black man in the middle of a field, the movies looked set in the 1800s. The Caucasian man said something and then suddenly started either cutting the black man with a sword or bull whipping him, and I remember a woman cleaning the wounds on the black mans back
Do you remember when you saw this film?
It’s most likely a film about slavery, but there are so many films that would fall into that category it’s difficult to say without a few more details. My first thought was 12 Years a Slave, but that’s fairly recent and I’m not sure when you saw it. There is a scene in there where a woman gets whipped very badly and a scene afterwards where she’s laying on the table getting her wounds cleaned up, but it doesn’t completely fit your description.
Roots… possibly??… as above said, so many slavery movies, could be any one of them