USS Winnebago was a double-turret river monitor, named for the Winnebago tribe of Siouan Indians, built for the Union Navy during the American Civil War. The ship participated in the Battle of Mobile Bay in 1864, during which she was lightly damaged, and the bombardments of Forts Gaines and Morgan as Union troops besieged the fortifications defending the bay. In early 1865, Winnebago again supported Union forces during the Mobile Campaign as they attacked Confederate fortifications defending the city of Mobile, Alabama. She was placed in reserve after the end of the war and sold in 1874. Description Winnebago was long overall and had a beam of . The ship had a depth of hold of and a draft of . She was 970 tons burthen and displaced . Her crew numbered 138 officers and enlisted men. The ship was powered by two 2-cylinder horizontal non-condensing steam engines, each driving two propellers, using steam generated by seven tubular boilers. The engines were designed to reach a top speed of . Winnebago carried of coal. The ship's main armament consisted of four smoothbore, muzzle-loading 11-inch Dahlgren guns mounted in two twin-gun turrets. Her forward turret was designed by James Eads and her rear turret by John Ericsson. Each gun weighed approximately and could fire a shell up to a range of at an elevation of +15°. The cylindrical turrets were protected by eight layers of wrought iron plates. The sides of the hull consisted of three layers of one-inch plates, backed by of pine. The deck was heavily cambered to allow headroom for the crew on such a shallow draft and it consisted of iron plates thick. The pilothouse, positioned behind and above the fore turret, was protected by of armor. Construction and service James Eads was awarded the contracts for all four of the Milwaukee-class ships. He laid down Winnebago at his Union Iron Works Carondelet, St. Louis in 1862. The first U.S. Navy ship to be named after the Indian tribe, she was launched on 4 July 1863 and commissioned on 27 April 1864. Initially assigned to the Mississippi River Squadron, Winnebago operated on the Mississippi River defending Union ships against Confederate raids and ambushes for several months. She was transferred to Rear Admiral David Farragut's West Gulf Blockading Squadron on 9 July, together with her sister . The ship required some time to refit at New Orleans and