8th Pennsylvania Reserve Regiment

8th Pennsylvania Reserve Regiment
Pennsylvania flag
Active	July, 1861 to May 24, 1864
Country	United States
Allegiance	Union
Branch	Infantry
Part of	1st Brigade, 2nd Division, I Corps, Army of the Potomac March to June 1862 2nd Brigade, 3rd Division, V Corps June to August 1862 2nd Brigade, 3rd Division, 3rd Corps, Army of Virginia August to September 1862 2nd Brigade, 3rd Division, V Corps, Army of the Potomac, September 1862 to February 1863 2nd Brigade, Pennsylvania Reserves Corps, XXII Corps, Department of Washington, February 1863 to April 1864 3rd Brigade, 3rd Division, V Corps, Army of the Potomac, April to May 1864
Engagements	Battle of Mechanicsville Battle of South Mountain Battle of Fredericksburg Battle of Spotsylvania Court House

The 8th Pennsylvania Reserve Regiment, also known as the 37th Pennsylvania Volunteer Infantry Regiment, was an infantry regiment of the northern Union Army during the American Civil War.

The regiment was organized at Camp Wilkins near Pittsburgh, Pennsylvania, with George S. Hays as colonel, S. D. Oliphant as lieutenant colonel, and J. B. Gardner as major. After training, it was sent to Washington, D.C. in late July, where it was assigned to the 1st Brigade of the Pennsylvania Reserves division, which became the Second Division, I Corps, Army of the Potomac. In May, it followed the rest of the division to the Peninsula, where the division became the Third Division, V Corps. On May 23, Gardner resigned and Captain S. M. Baily of company I was promoted to major in his place.

The regiment first came under fire at the Battle of Mechanicsville, where it lost nearly 100 men. When the rest of the army withdrew, Company F of the 8th Reserve, which had been sent forward as skirmishers, was not informed of the retreat and was left behind and captured by the Confederates. It also fought at the battles of Charles City Cross Roads and Glendale, losing over 200 additional men. After the regiment arrived at Harrison's Landing, both Hays and Oliphant resigned due to illness. Baily was promoted to colonel, Captain Lemon to lieutenant colonel, and Captain Robert E. Johnston to major.

The Pennsylvania Reserves Division was sent to the Army of Virginia in August as part of the III Corps. The 8th Reserve fought at the Second Battle of Bull Run, where it lost 52 out of 100 men, and again at South Mountain, where it lost another 54 men. At the Battle of Antietam, it fought on the Union right in the Cornfield, losing twelve killed and forty three wounded. It played a part in the Union breakthrough on the Confederate right at the Battle of Fredericksburg but lost heavily, especially in officers. Twenty-eight were killed, eighty-six wounded, and twenty-two captured. Baily, five captains, and five lieutenants were among the wounded. In February 1863, the regiment was ordered to Washington, where it was rested and brought back up to strength.