One of the deadliest and most pivotal conflicts in American history, the Battle of Antietam, took place on September 17, 1862, not far from Sharpsburg, Maryland, during the American Civil War. It was the war’s first significant battle fought on territory controlled by the Union.

General George B. McClellan of the Union Army of the Potomac faced up against General Robert E. Lee of the Confederate Army of Northern Virginia. There was a catastrophic loss of life on both sides due to the fighting’s intensity and brutality. The battle was the single bloodiest day of the Civil War, with roughly 23,000 casualties.

The Union won a strategic triumph at Antietam, despite the high casualties. It prevented a Confederate assault of the North by driving General Lee back to Virginia. After the victory, President Abraham Lincoln issued the Emancipation Proclamation, freeing all slaves in areas under Confederate control and forever changing the course of the war and the United States.

A full and compelling description of the Battle of Antietam can be found in a good history book. It examines the leadership choices, military maneuvers, and valorous actions of individual soldiers that determined the result of the conflict.