128th Pennsylvania Infantry in the American Civil War

Overview

The 128th Pennsylvania Infantry (Nine Months’ Service) was an infantry regiment from Pennsylvania that served in the Union Army during the American Civil War. Organized at Harrisburg between August 13 and 15, 1862, the regiment was primarily composed of men from Berks County, with additional recruits from Lehigh and Bucks Counties. The unit served in the Eastern Theater and was attached to the XII Corps, Army of the Potomac. Its service was marked by significant action at Antietam and Chancellorsville.

Organization & Service

The 128th Pennsylvania Infantry (Nine Months’ Service) was mustered into Federal service at Harrisburg, Pennsylvania, from August 13 to 15, 1862. Shortly after organization, the regiment moved to Washington, D.C., on August 16 and encamped at Arlington Heights, Fairfax Seminary, and Fort Woodbury, where it assisted in constructing fortifications.

The regiment was attached to Col. Crawford’s brigade, Williams’ division, in Mansfield’s corps (XII Corps). Its first major engagement was at the Battle of Antietam in September 1862, where it suffered heavy casualties. Following Antietam, the regiment was stationed at Sandy Hook and Maryland Heights for two months, remaining with the XII Corps under Gen. Williams after Gen. Mansfield was wounded at Antietam.

The 128th Pennsylvania arrived too late to participate in the Battle of Fredericksburg in December 1862 and spent the winter encamped at Fairfax Station and later at Stafford Court House. In January 1863, the regiment participated in the “Mud March.” In late April, it moved with the army for the Chancellorsville Campaign. On May 2, 1863, the regiment fought on the left of the Union line at Chancellorsville. That night, while returning to a previously held position that had fallen into enemy hands, 9 officers—including Col. Mathews and Lt. Col. Smith—and 225 enlisted men were captured. The remainder of the regiment was engaged the following day. After the battle, only 172 men reported for duty at Stafford Court House. The regiment was mustered out at Harrisburg on May 19, 1863, after the exchange of prisoners.

Engagements & Campaigns

• Battle of Antietam (September 17, 1862)
• Encampment at Sandy Hook and Maryland Heights (Fall 1862)
• Fredericksburg Campaign (arrived after main battle, December 1862)
• “Mud March” (January 1863)
• Chancellorsville Campaign (April–May 1863)
• Battle of Chancellorsville (May 2–3, 1863)

Casualties

At Antietam, the regiment suffered heavy losses. During the Battle of Chancellorsville, 9 officers and 225 enlisted men were captured. After the battle, only 172 men remained for duty. Specific figures for killed, wounded, and died of disease are not fully detailed in available primary sources.

Field Officers & Commanders

• Colonel Samuel Croasdale
• Colonel Joseph A. Mathews
• Lieutenant Colonel W. W. Hamersley
• Lieutenant Colonel L. Heber Smith
• Major Joel B. Wanner
• Major Cephas W. Dyer

Regimental Roster

The full roster of the 128th Pennsylvania Infantry (Nine Months’ Service), including officers and enlisted men, is available for genealogical and historical research. This roster provides names, ranks, and service details as recorded in official state and federal records.

To view the complete roster, visit the 128th Pennsylvania Infantry (Nine Months’ Service) Roster page.

Sources & References

• Official Records of the Union and Confederate Armies, Series I, Vol. XIX, Part 1, Part 2
• 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