Complex sentence: The white militias had come to the town and hunted down blacks after one white man was killed in a shootout at a church where black sharecroppers were meeting on issues related to organizing with an agrarian union.
Split into simpler sentences: The white militias had come to the town and hunted down blacks in retaliation for the killing of a white man. He was killed in a shootout at a church where black sharecroppers were meeting on issues related to organizing with an agrarian union.