Complex sentence: Morris served in the Civil War in the 1st Louisiana Native Guard, based in New Orleans, Louisiana, was one of the first all-black regiments to fight in the Union Army during the American Civil War.
Split into simpler sentences: Morris served in the Civil War in the 1st Louisiana Native Guard. The Guard, based in New Orleans, was one of the first all-black regiments to fight in the Union Army during the American Civil War.