Battle of Antietam
The Battle of Antietam (also known as the Battle of Sharpsburg, particularly in the South), fought on September 17, 1862, near Sharpsburg, Maryland, and Antietam Creek, as part of the Maryland Campaign, was the first major battle in the American Civil War to take place on Northern soil. It was the bloodiest single-day battle in American history, with about 23,000 casualties.
Coffin, Charles Carleton The Boys of '61; of, Four Years of Fighting. Personal Observation with the Army and Navy (Boston, MA: Estes and Lauriat, 1884)