Originally published on HistoryNet.com.
Published Online: March 27, 2012
Although it has long languished in the shadows cast by Antietam, the September 14, 1862, Battle of South Mountain was in itself a battle of great importance and profound consequence.
It was the first major battle fought north of the Potomac and it was there-and not at Antietam-where Lee's first invasion of Union territory was initially met-and turned back.
It was a daylong fight, spread out across many miles of rugged, mountainous terrain, as the two sides slugged it out for control of several key mountain passes.