1862
At the Battle of Gaines' Mill in the Seven Days Battles, Slocum's Division was sent to the support of Maj. Gen. Fitz John Porter and became hotly engaged, losing 2,021 men out of less than 8,000 present. The Vermont brigade of Smith's (2nd) Division took a prominent part in the fight at Savage's Station, the 5th Vermont losing 209 men in that action. The corps fought at other points during the Seven Days Battles, but at Malvern Hill it was held in reserve. At the Second Battle of Bull Run it was partially engaged, the First New Jersey Brigade of Slocum's (1st) Division having a sharp fight on August 27, at Bull Run Bridge, in which it lost 339 in killed, wounded, and missing, Brig. Gen. George W. Taylor, the brigade commander, receiving a mortal wound.
In the Maryland Campaign, Slocum's Division made a successful charge up the side of South Mountain at Crampton's Gap, driving the enemy from a strong position; Slocum's loss was 533 (113 killed, 418 wounded, 2 missing). The corps was under fire again at Antietam, but was only partially engaged; the 3rd Brigade (Col. William H. Irwin's) of Smith's Division, took an active part; however, the 7th Maine and 20th New York sustained severe losses.
Important changes in the corps now took place. It received a valuable accession by the transfer of Maj. Gen. Darius N. Couch's Division of the IV Corps, which now became the 3rd Division of the VI Corps, with Maj. Gen. John Newton in command. General Franklin was promoted to the command of the Left Grand Division, VI and I Corps, and General Smith succeeded to the command of the corps. General Slocum was promoted to the command of the XII Corps, and Maj. Gen. William T. H. Brooks succeeded Slocum in command of the 1st Division, while Brig. Gen. Albion P. Howe succeeded to the command of Smith's (2nd) Division.
Read more about this topic: VI Corps (Union Army)