Brotherhood of Death (1976)

A group of Black soldiers are home from the war and head to a small Southern town. The town is dominated by a group of Klansmen who keep the Black majority from voting or being treated like human beings. However, these newcomers convince the local population to register to vote so they can take back power and achieve justice. When hundreds show up to register, the Klan responds with violence. Eventually, though, the Black community has little choice other than fight back and the film ends with a small war between these combat vets and the Klan.

Unfortunately the movie Brotherhood of Death is not yet available on HBO Max.