Webster County is a county located in center of the U.S. state of Mississippi, bordered on the south by the Big Black River. As of the 2020 census, the population was 9,926.

Big Black River is a river in the U.S. state of Mississippi and a tributary of the Mississippi River. Its origin is in Webster County near the town of Eupora in the north central part of the state. From there it flows 330 miles (530 km) in a generally southwest direction until it merges with the Mississippi River 25 miles (40 km) south of the city of Vicksburg. It is the major contributor to the Big Black River Basin. It forms part of the northern border of Choctaw County, passes through Montgomery County, and forms the eastern border of Holmes County and the northern border of Claiborne County.