90th Pennsylvania Infantry in the American Civil War

Overview

The 90th Pennsylvania Infantry (Three Years’ Service) was an infantry regiment organized in Philadelphia, Pennsylvania, for Union service during the American Civil War. Recruitment began on October 1, 1861, and continued until March 10, 1862. The regiment was composed largely of men and officers with prior militia or short-term service, including veterans of the 19th and 17th Pennsylvania Infantry. The 90th Pennsylvania served primarily in the Eastern Theater, participating in major campaigns with the Army of the Potomac.

This regiment is distinct from any Pennsylvania infantry units of other service terms.

Organization & Service

The 90th Pennsylvania Infantry was organized in Philadelphia between October 1861 and March 1862, reaching a strength of approximately 900 men. The regiment departed for Baltimore on March 31, 1862, and then moved to Washington, D.C., and Aquia Creek Landing, where it was assigned to the 2nd Brigade (Gen. Ricketts), 2nd Division (Gen. Ord), 3rd Corps, Army of the Potomac. The brigade included the 26th and 94th New York and 88th Pennsylvania Infantry.

In May 1862, the regiment participated in operations in the Shenandoah Valley against Confederate forces under Stonewall Jackson. After returning to Waterloo in July, it joined General Pope’s campaign, moving to Cedar Mountain and serving as rear guard during the retreat across the Rappahannock. The regiment was engaged at Rappahannock Station and Thoroughfare Gap, and fought heavily at Groveton on August 29, 1862, suffering significant losses.

During the Maryland Campaign in September 1862, the 90th Pennsylvania fought at South Mountain and Antietam, with notable casualties at the latter. Afterward, the division was transferred to the 1st Corps under General Reynolds, and the brigade was reorganized to include Pennsylvania and New York regiments under Colonel Lyle. The regiment participated in the Battle of Fredericksburg in December 1862 as part of Franklin’s Grand Division, then moved to Belle Plain and performed fatigue duty at Pratt’s Point through early 1863, including the “Mud March.”

In late April 1863, the regiment took part in the Chancellorsville Campaign with the 1st Corps. Following the expiration of service for several nine-month regiments, the brigade was reorganized to include the 11th, 88th, and 90th Pennsylvania, 12th Massachusetts, and 97th New York. The 90th Pennsylvania entered the Gettysburg Campaign in June 1863, crossing into Pennsylvania on June 30 and engaging at Gettysburg with heavy losses.

After Gettysburg, the regiment participated in the pursuit of Confederate forces, then returned to Virginia for guard and drill duties at Bealeton Station and Stevensburg. It remained along the Rappahannock until October, then retreated to Centerville and worked on railroad repairs near Bristoe Station. The regiment participated in the Mine Run Campaign and wintered at Cedar Mountain.

In January 1864, the regiment was stationed at Culpeper, then camped on the Sperryville Pike. It became part of the 1st Brigade, 2nd Division, 5th Corps, and on May 4, 1864, joined the Overland Campaign. The regiment suffered severe losses at the Wilderness and continued to fight at Spotsylvania, North Anna River, Totopotomoy, and Bethesda Church. In June, the division was reorganized as the 3rd Division, 5th Corps, under General Crawford. The 90th crossed the James River and participated in the initial Petersburg operations, picket duty on the Jerusalem Plank Road, and the construction and garrisoning of Fort Davis. During the Weldon Railroad operations, Colonel Leech, Major Davis, and about 90 men were captured, with additional casualties.

Captain William P. Davis assumed command, and the regiment was employed in railroad destruction, road building, and reconnaissance to Poplar Spring Church. It later garrisoned Fort Dushane. On November 26, 1864, the original three-year term expired; non-reenlisted men were mustered out, and veterans and recruits were consolidated with the 11th Pennsylvania Infantry. The regiment was paid in Washington and formally disbanded in Philadelphia.

Engagements & Campaigns

• Shenandoah Valley operations (May 1862)
• Cedar Mountain
• Rappahannock Station
• Thoroughfare Gap
• Groveton (Second Bull Run Campaign)
• South Mountain
• Antietam
• Fredericksburg
• Chancellorsville
• Gettysburg
• Bristoe Campaign
• Mine Run Campaign
• Wilderness
• Spotsylvania
• North Anna River
• Totopotomoy
• Bethesda Church
• Petersburg operations
• Jerusalem Plank Road
• Weldon Railroad
• Poplar Spring Church

Casualties

The 90th Pennsylvania Infantry suffered heavy losses in several engagements. At Groveton, it lost about 200 men killed, wounded, or captured. At Antietam, the loss was 98. At Fredericksburg, approximately 90 men were lost. At Gettysburg, the regiment entered with 191 men and lost 100 killed, wounded, or missing. In the Wilderness, 124 out of 251 engaged were lost. During the Weldon Railroad operations, about 90 men were captured and around 20 killed or wounded. Total losses for the regiment are not fully detailed in all sources.

Field Officers & Commanders

• Colonel Peter Lyle
• Lieutenant Colonel William A. Leech
• Major Alfred J. Sellers
• Major Jacob M. Davis
• Captain William P. Davis (assumed command after Weldon Railroad operations)

Regimental Roster

The full roster of the 90th Pennsylvania Infantry (Three Years’ Service), including officers and enlisted men, is available on the regiment’s roster page. This resource provides names, ranks, and additional service details valuable for genealogical and historical research.

To view the complete roster, visit the 90th Pennsylvania Infantry (Three Years’ Service) Roster page.

Sources & References

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