What: Inconclusive; strategic Union victory
Where: Near Sharpsburg, Maryland.
Why: First significant Union victory, also first on Union soil.
When: September 17, 1862.
“I do order and declare that all persons held as slaves within said designated States, and parts of States, are, and henceforward shall be free.” – Abraham Lincoln, the Emancipation Proclamation.
The Battle of Antietam was one of the most crucial battles of the Civil War, often regarded as one of the turning points. Not only was it the bloodiest – with 22,717 men killed, wounded or missing in a single day – but it was the first major victory for the Union, and as a result gave Abraham Lincoln the confidence to announce his Emancipation Proclamation, freeing all the slaves in the ten Confederate states. This crucially discouraged British and French intervention and recognition of the Confederacy. General Robert E Lee advanced into the North on September 3, after their victory at Second Bull Run in an attempt to resupply his army and destroy Northern resolve to fight. By chance, McClellan’s Army of the Potomac stumbled upon Lee’s detailed battle plans wrapped around three cigars, learning he had divided his army. While Stonewall Jackson captured the Union arsenal at Harper’s Ferry, McClellan failed to act quickly enough, and after Lee slowed the Union pursuit in the Battle of South Mountain, he had the luxury of choosing the battlefield. The Union attacked Lee’s strong defensive positions, breaking the Confederate line in several places, but failed to capitalise. Despite having almost double the number of forces, McClellan failed to destroy Lee’s army, which withdrew back to Virginia, making the inconclusive battle a technical Union victory.