Choctaw County is a county located in the central part of the U.S. state of Mississippi. As of the 2020 census, the population was 8,246. Its northern border is the Big Black River, which flows southwest into the Mississippi River south of Vicksburg. The county seat is Ackerman. The county is named after the Choctaw tribe of Native Americans. They had long occupied this territory as their homeland before European exploration.