40th Pennsylvania Regiment Infantry, 11th PA Reserve in the American Civil War

Overview

The 40th Pennsylvania Infantry (also known as the 11th Pennsylvania Reserve) served as an infantry regiment for the Union during the American Civil War. Organized primarily from men in the western part of Pennsylvania, the regiment mustered at Camp Wright near Pittsburgh. It was mustered into United States service at Washington, D.C., on June 29–30, 1861, for a three years’ term. The regiment was part of the Pennsylvania Reserves division and saw service in both the Eastern and Overland theaters.

The 40th Pennsylvania Infantry was notable for its participation in major campaigns of the Army of the Potomac, including the Peninsula Campaign, Second Bull Run, Antietam, Fredericksburg, Gettysburg, and the Overland Campaign. The regiment suffered significant losses, particularly at Gaines’ Mill, and was eventually consolidated with the 190th Pennsylvania Infantry in June 1864.

Organization & Service

The 40th Pennsylvania Infantry (11th Pennsylvania Reserve) was organized at Camp Wright, near Pittsburgh, and left for Harrisburg on June 24, 1861. The regiment proceeded to Washington, D.C., and was mustered into federal service on June 29–30, 1861, for a three-year enlistment. Upon arrival, it joined the 2nd Brigade of the Pennsylvania Reserve Corps and was stationed at Great Falls, Maryland, where it engaged in a skirmish with Confederate forces across the Potomac River.

During the winter of 1861–62, the regiment was encamped near Langley, Virginia. Although present at Dranesville, the 2nd Brigade arrived too late to participate in the action. In the spring of 1862, the regiment joined the Peninsula Campaign under General Fitz John Porter, participating in the battles of Mechanicsville and Gaines’ Mill. At Gaines’ Mill, the regiment suffered heavy casualties and was largely captured after being surrounded, with only one company escaping due to special assignment.

The remaining company, under Captain Porter, fought at Glendale and participated in the Second Battle of Bull Run as part of the 3rd Brigade. The regiment, after being exchanged, rejoined the Army of the Potomac and fought at South Mountain, Antietam, and Fredericksburg. In February 1863, the regiment was ordered to Washington for rest and recruitment. It later rejoined the 5th Corps for the Gettysburg Campaign and participated in subsequent operations, including Bristoe Station, Rappahannock Station, and the Mine Run Campaign.

During the winter of 1863–64, the regiment was assigned to guard duty along the Orange & Alexandria Railroad, encamped at Warrenton Junction and Bristoe Station. In May 1864, the 40th Pennsylvania took part in the Overland Campaign, including the battles of the Wilderness and Bethesda Church. After its final engagement at Bethesda Church, the veterans and recruits were transferred to the 190th Pennsylvania Infantry. The regiment returned to Pittsburgh and was mustered out on June 14, 1864.

Engagements & Campaigns

• Skirmish at Great Falls, Maryland (1861)
• Peninsula Campaign (1862)
• Mechanicsville
• Gaines’ Mill
• Glendale (Company detached)
• Second Bull Run (Company detached)
• South Mountain
• Antietam
• Fredericksburg
• Gettysburg Campaign
• Bristoe Station
• Rappahannock Station
• Mine Run Campaign
• Wilderness
• Bethesda Church

Casualties

At Gaines’ Mill, the regiment lost 46 men killed and 109 wounded, with the majority of the regiment captured. Complete casualty figures for the entire service term are not fully detailed in available primary sources.

Field Officers & Commanders

• Colonel T. F. Gallagher
• Colonel Samuel M. Jackson
• Lieutenant Colonel James R. Porter
• Lieutenant Colonel Samuel M. Jackson
• Lieutenant Colonel Daniel S. Porter
• Lieutenant Colonel Robert A. McCoy
• Major S. M. Jackson
• Major Robert Litzinger
• Major Peter A. Johns
• Major James P. Speer
• Major Robert A. McCoy
• Major James C. Burke

Regimental Roster

The full roster of the 40th Pennsylvania Infantry (11th Pennsylvania Reserve) includes officers and enlisted men who served during its three years’ term. For researchers and genealogists, the complete roster provides names, ranks, and service details.

To view the full roster, visit the 40th Pennsylvania Infantry (Three Years’ Service) Roster page.

Sources & References

• Official Records of the Union and Confederate Armies, Series I, various volumes
• Pennsylvania Adjutant General’s Report
• Dyer, Frederick H., 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