An important battle of the Civil War was fought near here on September 4, 1862. General Robert E. Lee saw an opportunity to take his Army of Northern Virginia into Maryland and capitalize on recent battlefield successes. His plan was to force the Union into a demoralized position, possibly pressuring northern politicians to sue for peace, or at the least, to encourage Britain or France to aid the Confederacy.
But Lee didn’t count on one thing. A copy of his battle plans fell into the hands of Union commander Maj. Gen. George B. McClellan.
With knowledge of the plans, McClellan’s troops gained control of all three passes in these mountains. In terms of casualties, however, the losses were roughly even, about 2,900 casualties for the South and 2,340 for the North.
Lee was able to regroup his soldiers and prepare for another battle, which happened less than 10 miles away at Sharpsburg, starting on September 17, 1862. The resulting three-day fight, today known as the Battle of Antietam Creek, ended in the bloodiest single day of American military history. When it was over, 23,000 men had been killed or wounded.
Antietam ended in a draw, but the Confederates withdrew back into Virginia. That was enough to encourage President Abraham Lincoln to issue the Emancipation Proclamation.