Italian Americans in the Civil War are the Italian people and people of Italian descent, living in the United States, who served and fought in the American Civil War mostly on the side of the Union. A contingent of soldiers from the former Kingdom of the Two Siclies fought on the Confederate side, with most of these having been former prisoners of war who had fought against Giuseppe Garibaldi during his invasion of the Two Sicilies. Between 5,000 and 10,000 Italian Americans fought in the civil war.