The battle of Sharpsburg was the bloodiest single day engagement of the American Civil War. By what name is this battle also commonly known as?

Sharpsburg, Maryland was the closest town to the battle. However, the actual battle took place on both sides of a small creek which ran just outside of Sharpsburg - Antietam Creek.

The battle took place on September 17, 1862. This became the bloodiest day in American military history. The number of casualties was shocking: 22,717 Union and Confederate soldiers were killed, wounded or reported as missing.

Although there was no clear "winner" of this battle, it proved to be a great tactical victory for the forces of the Northern states; the Southern forces were halted after a string of stunning victories under their commander, Robert E. Lee, and were forced to retreat from Maryland and return to Virginia.