The 2nd Delaware Infantry was organized at Wilmington, Delaware from June 12 through October 7, 1861, and mustered in October 17, 1861, for three years' service under the command of Colonel W. Henry Wharton.
The regiment was attached to Dix's Command until June 1862.
3rd Brigade, 1st Division, II Corps, Army of the Potomac, to April 1863.
The 2nd Delaware Infantry mustered out of service July 1, 1864.
Veterans and recruits were transferred to the 1st Delaware Infantry Regiment.
Ordered to join the Army of the Potomac, on the Peninsula, Virginia, June 1862.
Covered Pope's retreat from Bull Run August 31-September 2.
Moved to Harpers Ferry September 22, and duty there until October 30.
Advance up Loudon Valley and movement to Falmouth, Virginia, October 30-November 17.
Pursuit of Lee to Manassas Gap, Virginia, July 5–24.
Jerusalem Plank Road, Weldon Railroad, June 22–23.