Alfred Pleasonton's Intelligence Contributions to the Battle of South Mountain

Alfred Pleasonton

Brig. Gen. Alfred Pleasonton is rarely thought of as an able intelligence officer. But like any Civil War officer, his share of bad days were occasionally intermixed with good ones. The evening of September 13, 1862 and the morning of the next day was one of his better performances in gathering and effectively utilizing intelligence.

In the hours before dusk of September 13, Pleasonton's cavalrymen drove Confederate cavalry from Hagan's Gap in Catoctin Mountain west of Frederick and then likewise secured Middletown from the gray horsemen. Pleasonton requested support from Ambrose Burnside in his rear. In the meantime, he pushed his troopers to the base of Turner's Gap in South Mountain itself.

At the crossroads town of Bolivar, Pleasonton dismounted some of his cavalry and pushed them up South Mountain north of the National Road. This movement produced minor skirmishing. Standing at the base of Turner's Gap, where the National Road crossed South Mountain, Pleasonton recognized the strength of the position and the difficulty any Federal force would have seizing it. Thus, Pleasonton also authorized reconnaissance efforts while in the area, from which he learned that two roads, one north of and one south of Turner's Gap, reentered the National Road on the west side of South Mountain behind the gap. Pleasonton believed these roads "would assist us materially in turning the enemy's position on both flanks."