Coosa County, named for the river on its western border, was created by the Alabama Legislature on December 18, 1832, from land ceded by the Creek Nation in the Treaty of Cusseta. Its name comes from the Native American word "kusha," believed to mean "canebrake." The Creeks had lived in great numbers in the region for generations before Alabama achieved statehood. The first county commissioners chose a site along the south bank of Hatchemadega Creek as the county seat and named it Lexington, but in 1835 the seat moved to its present location at Rockford. County commissioners authorized construction of a new jail in August 1839, and it was built of local stone and completed in 1842 at a cost of $2,745. Improvements, including new ironwork, were ordered in 1857. After operating for more than nine decades, the jail closed in 1938. A museum opened in the building in 1973, and the structure remains largely unchanged from its original construction. It is listed on the National Register of Historic Places as the oldest stone jail in Alabama.