Overview
The 31st Pennsylvania Infantry (also known as the 2nd Pennsylvania Reserve Infantry) served as an infantry regiment in the Union Army during the American Civil War. Raised primarily in Philadelphia, Pennsylvania, the regiment was part of the Pennsylvania Reserve Corps and was mustered into Federal service for a three-year term in August 1861. The unit saw extensive service in the Eastern Theater, participating in many of the major campaigns and battles of the Army of the Potomac.
Organization & Service
The 31st Pennsylvania Infantry (2nd Pennsylvania Reserves) began organizing in Philadelphia in the summer of 1861. The regiment moved to Harrisburg on July 24, 1861, but was quickly ordered to Baltimore and then Harper’s Ferry. Due to delays and confusion, many men returned home before the regiment was officially mustered in. The remaining companies were mustered into service at Hyattstown, Maryland, on August 16, 1861, for a three-year term. Several companies (B, F, G, and I) were initially disbanded for insufficient numbers, though Company B was later reformed and rejoined the regiment.
On September 25, 1861, the regiment was assigned to the 1st Brigade of the Pennsylvania Reserve Corps, becoming the 2nd regiment of the brigade. The 31st Pennsylvania saw its first major action at the Battle of Mechanicsville, where it sustained heavy fighting and received commendation for its conduct. The regiment was also engaged at Gaines’ Mill and Glendale, and held in reserve at Malvern Hill during the Seven Days Battles. It was under fire at Second Bull Run and Chantilly, and later fought near Frederick, Maryland, on the Old Hagerstown Road.
The regiment continued to serve with the 1st Brigade, Pennsylvania Reserves, at South Mountain, Antietam, and Fredericksburg. After a period of rest in Washington, D.C., a detachment from Company F, previously on artillery duty, rejoined the regiment in March 1863. During the Gettysburg Campaign, the regiment was attached to the 1st Brigade, 3rd Division, 5th Corps, and participated in the fighting at Gettysburg. The 31st Pennsylvania also took part in the actions at Bristoe Station and the Mine Run Campaign.
In the spring of 1864, during the Overland Campaign, several companies were detailed for guard duty, but the regiment continued to participate in the campaign’s battles until June 1, 1864. Its final engagement was at Shady Grove Church, after the expiration of its original term of enlistment. The regiment was mustered out at Philadelphia on June 16, 1864, with veterans and recruits transferred to the 191st Pennsylvania Infantry.
Research This Regiment Further
If you’d like to explore this unit’s history in more depth, regimental histories and Civil War reference works offer valuable detail.
Engagements & Campaigns
- Mechanicsville
- Gaines’ Mill
- Glendale
- Malvern Hill (in reserve)
- Second Bull Run
- Chantilly
- Old Hagerstown Road (near Frederick)
- South Mountain
- Antietam
- Fredericksburg
- Gettysburg
- Bristoe Station
- Mine Run Campaign
- Wilderness Campaign (including Shady Grove Church)
Casualties
According to available records, the 31st Pennsylvania Infantry (2nd Pennsylvania Reserves) suffered significant losses during its service. Exact figures for killed, wounded, and died of disease are not consistently reported in all primary sources. Fox’s Regimental Losses notes that the Pennsylvania Reserves, as a whole, sustained heavy casualties in several major battles. For the 31st Pennsylvania Infantry, the total number of killed and mortally wounded, as well as deaths from disease, is not fully detailed in surviving reports.
Some details are incomplete in surviving primary sources.
Field Officers & Commanders
- Colonel William B. Mann
- Colonel William McCandless
- Lieutenant Colonel Albert L. Magilton
- Lieutenant Colonel William McCandless
- Lieutenant Colonel George A. Woodward
- Lieutenant Colonel Patrick McDonough
- Major George A. Woodward
- Major Horace Neide
- Major Patrick McDonough
- Major Richard Ellis
Regimental Roster
The full roster of the 31st Pennsylvania Infantry (2nd Pennsylvania Reserves), including officers and enlisted men, is available for genealogical and historical research. The roster provides names, ranks, and service details for those who served in the regiment during its three-year term.
To view the complete roster, visit the 31st Pennsylvania Infantry (2nd Pennsylvania Reserves) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, various volumes and parts (Army of the Potomac, Pennsylvania Reserves)
- Pennsylvania Adjutant General’s Report, 1861–1865
- Dyer, Frederick H. A Compendium of the War of the Rebellion
- Fox, William F. Regimental Losses in the American Civil War
- The Union Army, Federal Publishing Company, 1908, Vol. 1