The City of McDonough is the county seat of Henry County. It was incorporated in 1823 and named for Commodore Thomas Macdonough, commander of American naval forces in Lake Champlain during the War of 1812.

The Brown House in McDonough is home to the Henry County Historical Society. Built in 1826, the building was the home of Andrew McBride, a Revolutionary War veteran from South Carolina. The home became the Brown House Hotel after it was expanded in 1874. The Romanesque Style Henry County courthouse, built in 1897, is also located in McDonough and listed on the National Register of Historic Places.