Overview
The 104th Pennsylvania Infantry (Three Years’ Service) was an infantry regiment organized at Doylestown, Pennsylvania, in September and October 1861. Composed almost entirely of men from Bucks County, the regiment served in the Union Army throughout the Civil War, primarily in the Eastern and Southern theaters. The unit was mustered into federal service for a three-year term and participated in several significant campaigns and operations, including the Peninsula Campaign, operations against Charleston, and the final assaults on Petersburg.
The regiment was noted for its gallantry at Fair Oaks and for its extended service in the Department of the South. The 104th Pennsylvania Infantry was mustered out on August 25, 1865, at Portsmouth, Virginia.
Organization & Service
The 104th Pennsylvania Infantry was organized at Doylestown, Pennsylvania, during September and October 1861, and mustered into United States service for three years. The regiment departed for Washington, D.C., on November 7, 1861, and spent the winter quartered at Georgetown.
In early 1862, the regiment was attached to the 1st Brigade, 3rd Division, 4th Corps, Army of the Potomac, and participated in the siege of Yorktown. It saw action at Savage Station and Fair Oaks, suffering significant losses at the latter. The regiment was held in reserve during the Seven Days’ Battles and arrived at Harrison’s Landing on July 3, 1862.
Afterward, the 104th Pennsylvania was stationed at Gloucester Point through the autumn and established winter quarters there. On December 28, 1862, it was ordered to Beaufort, North Carolina, and soon after moved to Hilton Head, South Carolina, to participate in operations against Charleston. The regiment camped on St. Helena Island until April 1863, when it took part in an unsuccessful movement against Charleston, then returned to Beaufort until July. During this period, Companies C and H were transferred to Battery Taylor and Company B to Battery Brayton.
In July 1863, the regiment moved to Folly Island and then to James Island, participating in the defense against an enemy attack on July 16. The following day, the troops withdrew to Folly Island. The 104th took part in the siege of Fort Wagner and was stationed on Morris Island after its evacuation by Confederate forces in September 1863, remaining there through the winter.
In December 1863, many members reenlisted as veterans. On April 26, 1864, Colonel Davis was assigned command of the district between St. Helena Sound and the Savannah River, with the regiment performing various duties. In June 1864, the regiment joined an expedition against Charleston, encountering enemy forces on John’s Island before returning to Hilton Head. At the end of July, the regiment was ordered to Florida, where it guarded the railroad between Jacksonville and Baldwin for a month.
On September 1, 1864, the regiment returned to Alexandria, Virginia. Non-reenlisted original members were mustered out at Philadelphia on September 30, 1864. The remaining veterans and recruits were consolidated into a battalion of five companies and sent to Harper’s Ferry, forming part of Heine’s Brigade. In November, the regiment was ordered to Philadelphia to maintain order during the presidential election, then returned to Harper’s Ferry. On November 22, it joined the Army of the Potomac at Petersburg, remaining there through the winter of 1864–65.
In April 1865, five new companies were added, restoring the regiment to full strength. The 104th Pennsylvania participated in the final assault on Petersburg and pursued retreating Confederate forces as far as Chesterfield Station. The regiment then returned to Petersburg, was ordered to Fortress Monroe on April 20, and was posted at Norfolk and Portsmouth until mustered out on August 25, 1865.
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
- Siege of Yorktown (April–May 1862)
- Battle of Fair Oaks (May 31–June 1, 1862)
- Battle of Savage Station (June 29, 1862)
- Seven Days’ Battles (reserve)
- Operations against Charleston, including St. Helena Island, Folly Island, James Island, and Morris Island (1863–1864)
- Siege of Fort Wagner (July–September 1863)
- Expedition to John’s Island (June–July 1864)
- Railroad guard duty in Florida (July–August 1864)
- Operations at Petersburg (November 1864–April 1865)
- Final assault on Petersburg (April 1865)
Casualties
According to official records, the 104th Pennsylvania Infantry suffered significant losses, particularly at Fair Oaks. Exact figures for killed, wounded, and died of disease are not consistently reported in all sources. Fox’s Regimental Losses and state reports may provide further detail, but some discrepancies exist in the totals.
Field Officers & Commanders
- Colonel William W. H. Davis
- Colonel Theophilus Kephart
- Lieutenant Colonel John W. Neilds
- Lieutenant Colonel Thompson D. Hart
- Lieutenant Colonel Theophilus Kephart
- Lieutenant Colonel J. McD. Laughlin
- Lieutenant Colonel T. B. Scarborough
- Major John M. Gries
- Major Edward L. Rogers
- Major Theophilus Kephart
- Major J. McD. Laughlin
Regimental Roster
The complete roster of the 104th Pennsylvania Infantry (Three Years’ Service), including officers and enlisted men, is available on the regiment’s roster page. This resource provides names, ranks, and service details for those who served in the unit.
To view the full roster, visit the 104th Pennsylvania Infantry (Three Years’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, various volumes and parts
- Pennsylvania State Adjutant General’s Reports
- 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, Volume 1