The Birth of a Nation (originally called The Clansman) is a 1915 American silent epic drama film directed and co-produced by D. W. Griffith and starring Lillian Gish. The screenplay is adapted from the novel and play The Clansman, both by Thomas Dixon Jr., as well as Dixon’s book The Leopard’s Spots. Griffith co-wrote the screenplay with Frank E. Woods and co-produced the film with Harry Aitken. It was released on February 8, 1915.
I know since it won a bunch of Oscars people like to call it a thriller but one character eats people, and another skins them alive and wears their skin as an outfit. I am going to go with a horror film for this one.