The Union Army, now under the command of General George B. McClellan, landed on the peninsula between the James River and York River, and marched west towards Richmond. The two armies fought a series of battles over a week known as the Seven Days Battle. On June 30, 1862, at the Battle of White Oak Swamp, Colvill received a bullet wound in the shoulder. He was sent to Baltimore where he spent the rest of the summer recuperating.