fort sumter is a island fortification in charleston, south carolina. the fort was where the american civil war began. on april 12, 1861, confederate artillery opened fire on the fort. the union garrison, under the command of major robert anderson, surrendered the fort 34 hours later. union forces attempted to take the fort back several times during the civil war. the fort was abandoned by confederate forces when the union army, under the command of maj. gen. william tecumseh sherman captured charleston in february 1865.