Army of the Potomac

On the morning of September 15, 1862, the Army of the Potomac pursued the retreating Confederates from South Mountain. Pleasonton's cavalry and the Second, First, and Twelfth Corps moved by Turner's Pass, Boonsboro, and Keedysville, while Sykes' Division of the Fifth Corps, the Reserve Artillery, and the Ninth Corps advanced by Fox's Pass and the Old Sharpsburg Road. The Sixth Corps and Couch's Division, attached to it, remained near Crampton's Pass. At Boonsboro, Pleasonton overtook the Confederate cavalry rear guard, attacked it, cut it off from the main body, and pursued it toward Hagerstown. Richardson's Division of the Second Corps, in the advance, followed closely and skirmished with the retreating infantry until it reached the ridge bordering the Antietam, where it formed line north of the Boonsboro Pike. From the crest of that ridge, Tidball's Battery and Pettit's Battery engaged Confederate artillery posted at and south of this point. French's and Sedgwick's Divisions of the Second Corps halted on either side of the pike midway between Keedysville and the Antietam. The First Corps took position east of the Upper Bridge, the Twelfth Corps halted near Keedysville, and Sykes' Division formed south of the Boonsboro Pike on Richardson's left. Late in the day the Ninth Corps encamped on Geeting's farm at the west base of Elk Ridge, and army headquarters were established at the Pry House.

Keedysville, Maryland · United States