USS Baron DeKalb (1861) was a City class ironclad gunboat constructed for the Union Navy by James B. Eads during the American Civil War. The USS Baron DeKalb, named after General Baron DeKalb of Hüttendorf near Erlangen, in present-day Bavaria, was originally named Saint Louis, and was one of seven City class ironclads built at Carondelet, Missouri and Mound City, Illinois, for the Western Gunboat Flotilla