Overview
The 131st Pennsylvania Infantry (Nine Months’ Service) was an infantry regiment organized in Pennsylvania for Union service during the American Civil War. The regiment was recruited from the counties of Northumberland, Lycoming, Mifflin, Union, and Snyder, and mustered into service at Harrisburg in early August 1862. Serving in the Eastern Theater, the 131st Pennsylvania Infantry participated in major campaigns of the Army of the Potomac during its brief but active service.
This unit served for a nine-month term and should not be confused with any other Pennsylvania regiments of different service terms.
Organization & Service
The 131st Pennsylvania Infantry (Nine Months’ Service) was organized at Harrisburg, Pennsylvania, in early August 1862. Colonel Peter H. Allabach commanded the regiment, with Lieutenant Colonel William B. Shaut and Major Robert W. Patton as principal field officers. After organization, the regiment was initially ordered to join the 3rd Provisional Brigade in Virginia, but was soon transferred to the force at Alexandria.
At the opening of the Maryland Campaign in September 1862, the regiment became part of the 3rd Division, 5th Corps, Army of the Potomac. The 131st arrived at Antietam too late to participate in the battle and encamped at Sharpsburg, Maryland. Its first major engagement was at the Battle of Fredericksburg in December 1862, where the regiment made a notable charge near the stone wall, suffering significant casualties. The regiment then established winter quarters near Falmouth, Virginia. In January 1863, it participated in Burnside’s second campaign, which was halted by poor road conditions. The regiment was next engaged at the Battle of Chancellorsville in May 1863. Following this action, the regiment returned to its camp, and its term of service expired on May 15, 1863. The 131st Pennsylvania Infantry was mustered out at Harrisburg on May 23, 1863.
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
- Maryland Campaign (arrived after the Battle of Antietam)
- Battle of Fredericksburg (December 1862)
- Burnside’s Second Campaign (January 1863, no major engagement)
- Battle of Chancellorsville (May 1863)
Casualties
At Fredericksburg, the regiment lost 177 men killed, wounded, and missing in about ninety minutes of combat. Total regimental losses for the full term of service are not fully detailed in all sources. Some details are incomplete in surviving primary sources.
Field Officers & Commanders
- Colonel Peter H. Allabach
- Lieutenant Colonel William B. Shaut
- Major Robert W. Patton
Regimental Roster
The full roster of the 131st Pennsylvania Infantry (Nine Months’ Service), including officers and enlisted men, is available for genealogical and historical research. The roster provides names, ranks, and additional service details where available.
To view the complete roster, visit the 131st Pennsylvania Infantry (Nine Months’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, Vol. 19, Vol. 21
- Pennsylvania Adjutant General’s Report, 1862–1863
- 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