Battle of South Mountain - Aftermath

Aftermath

By dusk, with Crampton's Gap lost and his position at Fox's and Turner's Gaps precarious, Lee ordered his outnumbered forces to withdraw from South Mountain. McClellan was now in position to destroy Lee's army before it could concentrate. Union casualties of 28,000 engaged were 2,325 (443 killed, 1,807 wounded, and 75 missing); Confederates lost 2,685 (325 killed, 1560 wounded, and 800 missing) of 18,000. The Battle of South Mountain was an important morale booster for the defeat-stricken Army of the Potomac. The New York World wrote that the battle "turn back the tide of rebel successes" and "the strength of the rebels is hopelessly broken." Lee contemplated the end of his Maryland campaign. However, McClellan's limited activity on September 15 after his victory at South Mountain condemned the garrison at Harpers Ferry to capture and gave Lee time to unite his scattered divisions at Sharpsburg for the Battle of Antietam on September 17.

The battlefields are preserved within the South Mountain State Park, Gathland State Park, and the Appalachian National Scenic Trail. Crampton's Gap Historic District and Turner's and Fox's Gaps Historic District are listed on the National Register of Historic Places.