Battle of South Mountain - Summary

Battle of South Mountain - September 14, 1862

South Mountain Battlefield

During the summer of 1862, the Confederate armies had been making advances against the Federals all along the 1,000-mile front between the two countries. Confederate General Robert E. Lee had been leading his Army of Northern Virginia on a three-month campaign and had essentially cleared Virginia of all Federal armies sent against him. After the Confederate victory at the Battle of 2nd Manassas, Lee found himself in the position to carry the war into the North by striking across the Potomac River into Maryland. After conferring with the Southern President, Jefferson Davis, Lee crosses the Potomac on September 4th, 1862, beginning what we now know as The Maryland Campaign.

As Lee and his army moves through the Maryland countryside and into the town of Frederick, Lee realizes that he has a problem. A 13,500 man Federal Garrison located at Harper’s Ferry, Virginia, sits at the northern end of the Shenandoah Valley, the route that Lee needs to open for both supply and communications. Expecting this garrison to vacate the town when Lee comes into Maryland, Lee is surprised to find that it is still there. Because of this, he issues Special Order 191 for the Army of Northern Virginia, in which he details plans to divide his army three ways. Half his army, under the commands of Brigadier General John Walker, Major General Lafayette McLaws and Major General Thomas “Stonewall” Jackson, was to surround and force the Federals at Harpers Ferry to surrender. Lee, along with Major General James Longstreet, would move through Turner’s Gap on South Mountain to the town of Boonsboro, while Major General Daniel Harvey Hill would follow the same route as Longstreet, but then, keep and eye to the south should any of the Federals try to escape from the garrison. Hill was also given the responsibility of watching the South Mountain Passes. The orders go out to all of Lee’s generals, and his army begins their westward movement towards South Mountain and Harper’s Ferry.

While all this was going on, President Abraham Lincoln was looking for a General to lead the Federal Army out in pursuit of Lee. The Federals, having just suffered a major defeat at the Battle of 2nd Manassas, needed a General who could get the army reequipped and back out into the field in a very short time. Lincoln called upon General George B. McClellan to rebuild this defeated and demoralized army and drive the Confederates out of Maryland. McClellan formally received command of the Army of the Potomac on September 8th and set out after Lee, reorganizing his army while on the move across Maryland. McClellan arrives in Frederick on September 13, just behind the Confederates. While here, McClellan begins making plans for a movement of his army towards South Mountain. While he is doing this, he is brought a copy of Special Order 191 that was somehow left behind by the Confederates in a field near the Monocacy River. Armed with this new information, McClellan knows that this is the time to strike.

The Battle of South Mountain begins around 9:00 a.m. as the Federal IX Corps moves up the side of the mountain. The Kanawha Division, led by future President Lt. Colonel Rutherford B. Hayes, moves to the south towards Fox’s Gap in an effort to gain and turn the Confederate right flank. Waiting for these Ohio regiments are the five regiments of Brigadier General Samuel Garland’s North Carolinians. A section of Major General J.E.B. Stuart’s Horse artillery, commanded by Captain John Pelham, open the hostilities by firing at the advancing blue columns, and by 10:00 the fighting has become general along the entire line on this portion of the field. It is at this time that Lt. Col. Hayes is severely wounded and has to be taken from the field to the nearby town of Middletown for recuperation. Shortly after Hayes wounding, Confederate Brig.Gen. Garland was leading additional regiments into the battle through Daniel Wises’ south field. It was here that the General is mortally wounded. As he falls from his horse, his staff gathers up the General and rushes him towards Turner’s Gap, a mile to the north. Moments later, the Ohio regiments launch a headlong attack toward the Confederates positioned behind a stone wall along the top of the mountain, gaining their flank and turning them back toward Fox’s Gap. Eventually, the weight of the Federal attack breaks the Confederate line, sending them down over the west side of the mountain in retreat. By noon, the Federals hold Fox’s Gap. However, Federal Brigadier General Jacob Cox feels the position is too far extended and he calls his troops back south of the road to a position along a stonewall at the south end of Wises’ south field to wait until the rest of the IX Corps can pull itself up onto the mountain. By doing this, the Confederates are once again able to occupy the gap. The brigades of Brigadier General Roswell Ripley, Brigadier General George B. Anderson, Colonel George T. Anderson and Brigadier General Thomas Drayton move along the woods road from Turner’s Gap back into Fox’s Gap and form up in the Sharpsburg Road, facing south towards Cox’s men. The Confederates move out of the road in a counterattack intent on driving the Federals off the mountain. Unfortunately for the Confederates, the attack goes badly almost from the start. Brigades become separated from each other and some become lost in the dense Laurel thickets on the mountain. The 17th Michigan Infantry comes up onto the mountain and partially surrounds the 50th and 51st Georgia regiments in the Sharpsburg Road and nearly wipes them out. Drayton’s Brigade takes the brunt of the Federal fire and is driven from the top of the mountain suffering 51% casualties. As the shadows begin to lengthen across the gap, Major General Jesse Reno rides north along the Woods Road to see if it is practicable to continue pushing towards Turner’s Gap and possibly surrounding the Confederates there. Just as he rides along this road, several volleys of fire from Brigadier General John B. Hood’s Texas Brigade meet him. Two of these bullets strike General Reno, mortally wounding him. He is taken from the field down the east side of the mountain where he dies under an Oak tree.

As the action at Fox’s Gap heats up again, the Federal I Corps arrives on the field having marched all the way from Frederick that day, a distance of about eleven miles. Moving along the National Road to the small town of Bolivar, most of the I Corps moves north towards the Frosttown Gap to try and gain the Confederate left flank and turn it just as they had done to the Rebel right. One brigade, commanded by Brigadier General John Gibbon, is left behind on the National Road to move toward the Confederate center at Turner’s Gap. Below the Gap is the Georgian Brigade of Colonel Alfred Colquitt waiting for the Federals. Off to the north, once the rest of the I Corps has got itself into position, both groups step off on their attack up the side of the mountain. Facing the Federal advance on this part of the field is Brigadier General Robert Rodes with his Alabama Brigade. Using the terrain to their advantage, the Confederates are able to slow the Federal attack, but not hold them. Eventually the weight of the Federal attack overwhelms the Confederates pushing them back. At this moment, the last remaining elements of Longstreet’s command arrive on the field driving into the Federals and stopping their advance. To the south, along the National Road, Gibbon’s brigade of westerners push back the skirmishers from Colquitt’s brigade and start to take heavy casualties of their own. Colquitt’s line bends, but does not break, and they are able to hold their line. As darkness falls, the westerners take stock of their casualties. In total, Gibbons men lose a quarter of their strength on the rocky slopes of South Mountain. That night, the men are told to hold their ground by the bayonet as they sleep on their arms.

South Mountain Battlefield

Around noon and six miles to the south of Turner’s Gap, the Confederate forces at Crampton’s Gap see moving toward them the entire strength of the Federal VI Corps. Commanded by Major General William B. Franklin, the VI Corps numbers somewhere around 10,000 effectives. The Confederates, on the other hand, only number around 1,000 men, most of which are positioned behind a stonewall at the foot of the mountain along Mountain Church Road. A mile south of Crampton’s Gap is Brownsville Pass, being held by Confederate Brigadier General Paul Semmes with some infantry and a mixture of artillery. Semmes believes that, since the Confederate forces under McLaws had traveled by way of this pass on their way to Maryland Heights overlooking Harper’s Ferry, that the Federals will also try and force their way through this pass. Unknown to him, General McClellan has ordered Gen. Franklin to take Crampton’s Gap to “Drive a wedge between the two halves of Lee’s army and defeat him in detail.” Once over the mountain, Franklin is further ordered to turn south and hit McLaws in the rear, driving him into the Potomac and releasing the garrison now being surrounded at Harper’s Ferry. It is an ambitious plan and Franklin is not up to the task. Once in Burkittsville, the small town at the foot of South Mountain at Crampton’s Gap, Franklin takes nearly four hours to decide on a plan of attack and put it into motion. Once the Federal lines move forward, they find that there are not as many Confederates behind the stonewall as they thought. The entire Federal line charges forward, breaking the Confederate line and sending them scurrying towards the top of the gap. Just as this line is breaking, Brigadier General Howell Cobb arrives at the top of the gap with his Georgia and North Carolina regiments. Two of the regiments, Cobb’s Legion and the 16th Georgia, file into Whipps Ravine in front of the Federals and fire volleys into them to try and slow their advance. Eventually these regiments become nearly surrounded and are nearly decimated. The Confederates try to make one last stand in the gap, but these few defenders are quickly overpowered as well and sent running for their lives down the western slope of the mountain. Two guns with the Troup Light artillery had come into the gap along with Cobb. One of them has to be left behind as the axle breaks under it while it is being withdrawn off the field. McLaws arrives on the field and throws a line of infantry across the valley, anchored at both ends with artillery, and waits for the morning to come.

The night of September 14, 1862 found Lee in a difficult position. The days fighting has ended with over 6,000 casualties between the two armies. Lee’s flanks on the mountain had been turned both to the north and south of Turner’s Gap and Longstreet reports that the Confederate position is untenable. Lee issues orders to his generals that, “The day has gone against us, and this army will move by way of Sharpsburg and cross the river.” The river he speaks of is the Potomac River. This is not an easy decision for Lee when just two weeks earlier, he had entered Maryland with such high goals. However, Lee has not heard from Jackson at Harper’s Ferry for several days and he needs to preserve his army. He moves towards the town of Sharpsburg and takes up a position along the banks of the Antietam Creek where he can better defend himself should McClellan attack. However, early the next morning on September 15, Jackson is finally able to force the surrender of the Federals in Harper’s Ferry. Jackson sends word to Lee about his victory, and lee orders Jackson and all the other Confederate forces to assemble near Sharpsburg where Lee still hopes to pull out a victory on Northern soil. The result of which is the Battle of Antietam on September 17, 1862, totaling 23,110 casualties for both armies. Neither army takes up the offensive on the 18th, and Lee withdraws back across the Potomac through the night into the morning of the 19th, ending the Maryland campaign.

President Lincoln takes the opportunity with the Federal victories to issue the Emancipation Proclamation that ties the issue of slavery into the war. With this move, Lincoln assures that this will be an American war, since England and France have abolished slavery many years before and will not recognize a government that supports that institution.

Confederate General James Longstreet would later write of the Maryland Campaign,” The razing of the walls of Jericho…was scarcely a greater miracle than the transformation of the conquering army of the South into a hoard of disordered fugitives before an army that two weeks earlier was flying to cover under it’s homeward rampart.”