IV Corps (Union Army) - IV Corps (Eastern Theater)

IV Corps (Eastern Theater)

The IV Corps, Army of the Potomac, was created on March 13, 1862, and placed under the command of Erasmus D. Keyes, who had commanded a brigade at First Bull Run. It consisted initially of three divisions, under Darius N. Couch, Silas Casey, and William F. “Baldy” Smith. Couch's division was transferred to join VI Corps during the Antietam Campaign and remained with them for the duration of the war. The corps' peak strength (in early 1862) was 37,000 men.

The corps took part in George B. McClellan's Peninsula Campaign of 1862, playing a major role in repulsing Confederate attacks at Seven Pines and Malvern Hill. After the campaign, IV Corps remained on the Peninsula, with Couch's division later detached. The corps was attached to the Department of Virginia under John A. Dix, and took part (along with VII Corps) in minor diversionary actions against Richmond during the Gettysburg Campaign. The corps was officially discontinued on August 1, 1863.