While the Battle of Antietam was the most important conflict that took place in Maryland, it critical to avoid overlooking the battle that forced the Union and Confederate forces to meet at Antietam Creek on September 14, 1862 along the gaps of South Mountain. As an extension of the Blue Ridge Range, the South Mountain was a heavily wooded and rocky terrain that ran southwest from Pennsylvania down to the Potomac River near Harpers Ferry. To the east of the mountain was the town of Frederick, Maryland, less than 50 miles from Washington, D.C.
The fighting that occurred on the long Sunday was fierce and constant. Artillery, musket, bayonet, and fists were all employed as weapons, which resulted in a tremendous number of casualties. The Union forces engaged that day totaled 28,000 and by nightfall 2,325 were listed as casualties. The Confederate Army utilized 18,000 troops and suffered a loss of 2,685 men, an astounding 800 of which were listed as missing.These men, many of whom are lost to history, engaged in a battle that led directly to the bloodiest single day in U.S. military history, Antietam, which in turn led to a new war aim for President Abraham Lincoln. The Battle of South Mountain, therefore, was the catalyst for the events that forever altered the course of the Civil War.