Sauk County is a county in Wisconsin. It is named after a large village of the Sauk people. As of the 2020 census, the population was 65,763. Its county seat and largest city is Baraboo. The county was created in 1840 from Wisconsin Territory and organized in 1844. Sauk County comprises the Baraboo, WI Micropolitan Statistical Area and is included in the Madison metropolitan area.