Battle of Mobile Bay By lesliejo Aug 3, 1864 Union forces land on Dauphin Island and invest Fort Gaines Period: Aug 3, 1864 to Aug 23, 1864 Battle of Mobile Bay Aug 5, 1864 Battle of Mobile Bay Aug 5, 1864 Confederates surrender Fort Gaines Aug 9, 1864 Seige of Fort Morgan begins Aug 23, 1864 Fort Morgan surrenders to Union forces