The Battle of Antietam, also called the Battle of Sharpsburg, took place during the American Civil War on September 17, 1862, between Confederate General Robert E. Lee's Army of Northern Virginia and Union Major General George B. McClellan's Army of the Potomac near Sharpsburg, Maryland, and Antietam Creek. After a victory at Manassas in August, General Lee marched his Army of Northern Virginia into Maryland, hoping to find men and supplies. By September 15, both armies had established battle lines west and east of Antietam Creek near the town of Sharpsburg, Maryland. At dawn on September 17, General Joseph Hooker's troops mounted a powerful first Union assault on Lee's army.
About 40,000 Confederates battled against the 85,000 of the Union Army under General George B. McClellan. 23,000 soldiers were killed, wounded or missing after twelve hours on September 17, 1862. It was General Robert E. Lee's first invasion into the North. It was part of the Maryland Campaign of 1862. The battle began at dawn when Union General Hooker's artillery began shelling "Stonewall" Jackson's men in the Miller cornfield to the north of the town. After the battle some said it looked like the corn was cut as if from a large knife from all of the firing.
At an old sunken road separating the Roulette and Piper farms fighting raged for over 4 hours and (afterwards was known as Bloody Lane).
To the south General Ambrose Burnside's troops had been trying to cross a bridge over Antietam Creek for hours in vain and is now known as Burnside's Bridge. More men were killed, wounded or missing at Antietam on September 17, 1862, than on any other single day during the Civil War. The battle was also instrumental in prompting President Abraham Lincoln to issue the Emancipation Proclamation, which, on January 1, 1863, declaring freedom for all slaves in States still in rebellion against the United States.