The5th New Hampshire Infantry Regimentwas an infantry regiment that served in the Union Army during the American Civil War. The regiment has the unfortunate distinction of having sustained the greatest total loss in battles of any infantry or cavalry regiment in the Union Army, with a total of 295 killed and 756 wounded, for a total of 1,051 men.The 5th New Hampshire Infantry was organized in Concord, New Hampshire and mustered in for a three-year enlistment on October 22, 1861, under the command of Colonel Edward Ephraim Cross.The regiment was attached to Howard's Brigade, Sumner's Division, Army of the Potomac, to March 1862. 1st Brigade, 1st Division, II Corps, Army of the Potomac, to July 1863. Concord, New Hampshire, Department of the East, to November 1863. Marston's Command, Point Lookout, Maryland, to May 1864. 1st Brigade, 1st Division, II Corps, Army of the Potomac, to June 1865.The 5th New Hampshire Infantry mustered out of service June 28, 1865, and was discharged July 8, 1865.