During the afternoon of September 14th, 1862, General McClellan, who was commanding the Army of the Potomac knew that the Confederate Army was divided, and he wanted to pounce each individual portion before it had time to concentrate. Standing in McClellan’s way were two things. The first was South Mountain, a mountain range that divides Frederick and Washington Counties, or Eastern Maryland from Western Maryland. The second was a meager Confederate force of about 1,500 defending the mountain gaps from Frostown to Fox’s Gap. Seven miles further to the south was another 1,500 Confederate soldiers guarding the backdoor to Harper’s Ferry at Crampton’s Gap and Brownsville Pass. With both of these issues facing McClellan, he knew he had to act now.
Thinking that Turner’s Gap would be heavily defended, McClellan decided he would side step it and move his army through Fox’s Gap to the south, and Frostown to the north of Turner’s Gap. Here McClellan would face a major obstacle. Confederate General Daniel H. Hill had already sent a brigade under General Samuel Garland to Fox’s Gap and another brigade under Colonel Alfred Colquitt below Turner’s Gap on the National Road. North of Turner’s Gap, Hill had ordered General Robert Rodes’ Alabama Brigade to occupy the area that the Virginians and South Carolinians would later become engaged in. To make matters worse, in the Middletown Valley McClellan’s army was in view of the Confederate artillery that had massed at the summit of Turner’s Gap under the command of Captain John Lane. Eventually, more artillery support arrived as Lieutenant Colonel Allen S. Cutts’ Artillery Battalion arrived and deployed on the heights of Turner’s Gap. To attack such a position would almost be suicide.
During the mid afternoon, the Union 1st Corps under the command of General Joseph Hooker arrived at Bolivar, a town with a distinct crossroad. Bolivar is located between Middletown and South Mountain. Taking the Mount Tabor Road on the right from Bolivar, he would soon send his Corps into battle where a small force of Confederate soldiers guarded the area. After marching on Mount Tabor Road, General John Gibbon’s Brigade, already known by that time as the Iron Brigade for their assault at Manassas a few weeks before, was recalled and ordered to hit the Confederate defenses along the National Road. As Hooker advanced on the small hamlet of Frostown, he would soon be in position to hit the small Confederate force under General Robert Rodes, who was being reinforced by other brigades of Confederate infantry at that time.
Using Frostown Road, Hooker’s Corps deployed. General George Meade and his division deployed to the right of Frostown Road, while General John Hatch deployed to the left of Frostown Road. Situated in the center, and held in reserve was the division under General James Rickett’s. As General Hatch’s division began to climb the rugged mountainside Private Uberto A. Burnham of the 76th New York, Hofmann’s Brigade recalled: “The mountain was quite steep. When we were about half-way up we halted a few minutes to rest. The sun had gone down behind the mountain. We were marching in the shadow. The sun lighted up the valley behind us. It was a beautiful sight, with farm houses, grain fields, orchards, groups of staff officers, and columns of troops in motion, but I cannot say I enjoyed the scene. I felt the importance of the big task before us.”
Private Burnham continued: “A little further up the mountain was a comparatively level place planted with corn, which had been fenced in. I saw the skirmishers go in the field, and thought they would perhaps find some of the enemy there, but they did not. I saw their bright uniforms going over the fence on the further side. Three women came down the side of the mountain on horseback by a diagonal path and passed in front of the regiment.”
As Hatch’s boys in blue were ascending the mountain, the men noticed that the eastern side of the mountain was cleared to the summit where it turned into a wooded area about 200 yards wide. From there a cornfield appeared, then another wooded area, and from there a wide path to Turner’s Gap was revealed. This was the area that General Hatch’s Division was to take possession of.
General Hatch, being newly appointed deployed his division. Covering his left flank was General Walter Phelps’ First Brigade, who commanded the following regiments: the 22nd New York Infantry, 24th New York Infantry, 2nd United States Sharpshooters, 30th New York Infantry, and the 84th New York Infantry. To their right was General Marsena Rudolph Patrick’s Third Brigade which consisted of the 21st New York Infantry, 23rd New York Infantry, 35th New York Infantry, and the 80th New York Infantry. Held in reserve, in the rear of Hatch’s Division was the Second Brigade under General Abner Doubleday, who commanded the 56th Pennsylvania Infantry, 76th New York Infantry, 7th Indiana Infantry, and the 95th New York Infantry.
General Marsena Patrick’s Third Brigade deployed and held the right of Hatch’s Division. General Patrick sent out the 21st New York ahead of his brigade. Upon deployment, General Hatch ordered the rest of General Patrick’s Brigade to ascend South Mountain. The 35th New York deployed to the left, overlooking the road, and without unslinging their knapsacks, climbed the mountain. Soon before reaching the summit, the 35th New York lost site of the 21st New York, and the 80th New York was ordered to plug the hole. The 23rd New York supported the 35th New York during the deployment. By this time Colonel Phelps arrived in support of the line.
Upon deployment, Colonel Phelps noted that the woods and the nature of the ground gave them protection from Lieutenant Colonel Cutts’ Artillery Battalion, which was posted and firing on his left. From there Colonel Phelps moved forward, marching toward the summit where the road was located. As they moved forward, Colonel Phelps requested that General Patrick deploy his skirmishers. As Phelps moved, the ground gave him cover, thus he was unobserved by General Richard Garnett’s Confederate Brigade. Garnett’s brigade was posted behind a fence and cornfield, with artillery behind them in an open field, on higher ground.
General John Hatch followed Phelps just as the battle had begun, and ordered the men forward during a deadly fire. Soon a bullet struck General Hatch and he was removed from the field where General Abner Doubleday took command. Phelps’ men continued to the top and began to engage the Confederates. Phelps’ advance continued until he stopped in an area where an abrupt rise of ground gave his men shelter. Once there, the 84th New York (14th Brooklyn) advanced to the left to hit the right of Garnett’s Brigade, where the 8th Virginia Infantry was posted, hitting the Confederate ranks with great musketry. During the deployment of Phelps’ Brigade, the 2nd U.S. Sharpshooters were detached and ordered to preceed up a steep ravine, where they rendered valuable service.
While Patrick’s and Phelps’ brigades were in the beginning phases of the battle, the 21st New York under the command of Colonel William F. Rogers charged up the hill and took possession of a fence near the cornfield, where they began picking off the Confederate cannoneers. Lieutenant Colonel Theodore Burr Gates, commanding the 80th New York Infantry was ordered by General Patrick to support the 35th New York, which by that time, was thrown forward near the road as skirmishers. The road was in site and orders came for the 80th New York to support the 21st New York, which was already charging up the mountain toward the cornfield. Skirmishers were again deployed until the rest of the 80th New York was in place. Soon a volley from the New Yorkers poured into the Virginians, who were now lying behind a fence by the cornfield. The 14th New York came onto line and engaged in the battle, helping to push Garnett’s Confederate soldiers back.
As Hofmann’s Brigade came to the summit in support of Phelps and Patrick, their officer’s ordered the knapsacks to be unslung, and just then came a clash of musketry. The officers soon ordered bayonets to be fixed, and forward at a charge they went. When this occurred the Confederate troops began to fall back through the wooded area, taking position in the open field. The Union line came to the edge of the woods, to an old rail fence and halted. Private Burnham recalled: “The broken fence was about knee high, but seemed to give some protection.”
The Union troops pushed the Confederates back through the field to the stone fence where the Confederate soldiers held that position, and soon Hatch’s boys occupied the open fields on the mountaintop. Phelps’ Brigade held that position until General James Rickett’s Division arrived, and Phelps’ pulled back to a more supportive role.
Darkness came long before the firing had ceased. During the night after the battle died down, Union troops slept on their arms, ready for any attack that may come. But such an attack never came, as the Confederate forces fell back from the heights of Tuner’s Gap and began to march toward Boonsboro, where they were ordered to begin their march to Sharpsburg. The fighting that took place at Frostown was fought on some of the most rugged mountain terrain in the area. Those men, officers, and enlistees alike, all mention the treacherous rocky terrain.