Overview
The 9th Pennsylvania Infantry (Three Months’ Service) was an infantry regiment organized for short-term Federal service at the outset of the Civil War. Raised from several counties across Pennsylvania—including Chester, Armstrong, Cumberland, Lehigh, Northampton, Schuylkill, and Delaware—the regiment was mustered into United States service at Harrisburg between April 22 and 24, 1861. It served in the Union Army, primarily in the Department of Pennsylvania, during the early months of the conflict.
This unit is distinct from any later regiments with similar designations that served for longer terms.
Organization & Service
The 9th Pennsylvania Infantry (Three Months’ Service) was organized at Harrisburg, Pennsylvania, in late April 1861, in response to President Lincoln’s initial call for volunteers. The regiment was composed of companies recruited from multiple counties and was mustered into service for a term of three months.
On May 4, 1861, the regiment arrived at West Chester, Pennsylvania, where it remained in camp until May 26. It then moved to Wilmington, Delaware. On June 6, the regiment joined Major General Robert Patterson’s command at Chambersburg, Pennsylvania, and was assigned to the 4th Brigade, 1st Division, under Brigadier General Dixon S. Miles. Ten days later, the regiment crossed the Potomac River and camped near the riverbank. When General Miles departed for Washington, the 9th Pennsylvania reported at Williamsport, Maryland. The regiment remained near the Potomac until July 1, when it advanced to Martinsburg, Virginia (now West Virginia). It participated in subsequent movements to Bunker Hill and Charlestown. The regiment returned to Harrisburg and was mustered out of service on July 29, 1861.
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
- Duty at West Chester, Pennsylvania (May 1861)
- Duty at Wilmington, Delaware (May–June 1861)
- Operations with General Patterson’s Army in the Department of Pennsylvania (June–July 1861)
- Advance to Martinsburg, Virginia (July 1861)
- Movements to Bunker Hill and Charlestown (July 1861)
Casualties
Specific casualty figures for the 9th Pennsylvania Infantry (Three Months’ Service) are not detailed in the primary sources. The regiment’s term of service was brief and it did not participate in major battles during its enlistment.
Field Officers & Commanders
- Colonel H. C. Longnecker
- Lieutenant Colonel William H. H. Hangen
- Major Charles Glantz
Regimental Roster
The complete roster of officers and enlisted men who served in the 9th Pennsylvania Infantry (Three Months’ Service) is available for genealogical and historical research. The roster includes names, ranks, and company assignments as recorded at the time of service.
To view the full roster, visit the 9th Pennsylvania Infantry (Three Months’ Service) Roster page.
Sources & References
- The War of the Rebellion: Official Records of the Union and Confederate Armies, Series I, Vol. 2
- Pennsylvania Adjutant General’s Report, 1861
- Dyer, Frederick H., A Compendium of the War of the Rebellion
- Federal Publishing Company, The Union Army, Vol. 1 (1908)