Important battles in the Tennessee and Cumberland Rivers campaign were the capture of Fort Henry and Fort Donelson, where the Union forces were under the direct command of Brigadier General U.S. Grant, who reported to Major General Halleck, and the naval forces of the Western Gunboat Flotilla, predecessor of the Mississippi River Squadron, were led by Flag Officer Andrew H. Foote. Key military actions along the Mississippi River included the Island No. 10, the Battle of Memphis, Siege of Vicksburg