Premise: Campbell County is a county located in the U.S. state of South Dakota. As of the 2010 census, the population was 1,466, making it the fifth-least populous county in South Dakota. Its county seat is Mound City. The county was created in 1873 and organized in 1884. It is named after Norman B. Campbell, a Dakota Territory legislator in 1873 and son of General Charles T. Campbell.
Hypothesis: Mound City is in South Dakota