Overview
The 4th Ohio Infantry (Three Years’ Service) was an infantry regiment from Ohio that served in the Union Army during the American Civil War. Organized at Camp Dennison, Ohio, in June 1861, the regiment was mustered in for a three-year term. The 4th Ohio participated in numerous major campaigns and battles in both the Eastern and Western Theaters, earning distinction for its service and actions in several key engagements.
This unit is distinct from the 4th Ohio Infantry (Three Months’ Service).
Organization & Service
The 4th Ohio Infantry (Three Years’ Service) was organized at Camp Dennison, Ohio, in June 1861. The regiment was mustered into Federal service for a three-year term. Throughout its service, the 4th Ohio was attached to various brigades and divisions, primarily within the Army of the Potomac and later the Army of the James.
The regiment participated in early operations in western Virginia, including actions at Rich Mountain and Romney. It later moved to the Shenandoah Valley, taking part in the battles of Winchester, Front Royal, and Port Republic. The 4th Ohio fought in the Maryland Campaign at Antietam, and subsequently in the battles of Fredericksburg and Chancellorsville. At Fredericksburg, the regiment received the first fire of the Confederate artillery on the right of the Union line. At Chancellorsville, it captured a stand of colors and over 100 prisoners, including nine commissioned officers.
During the Gettysburg Campaign, the 4th Ohio was among the regiments that retook Cemetery Hill after Confederate forces had temporarily gained ground. The regiment continued to serve in the Overland Campaign, fighting at Bristoe Station, Mine Run, Wilderness, Po River, Spotsylvania, North Anna River, Totopotomy, Cold Harbor, Petersburg, Deep Bottom, and Reams’ Station.
The original members (except veterans) were mustered out on June 21, 1864, upon expiration of their term. The remaining veterans and recruits, along with those from the 8th Ohio Infantry, were consolidated to form the 4th Battalion Ohio Infantry on June 26, 1864. This battalion was mustered out on July 12, 1865, in accordance with War Department orders.
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
- Rich Mountain (West Virginia)
- Romney (First and Second, West Virginia)
- Winchester (Virginia)
- Front Royal (Virginia)
- Port Republic (Virginia)
- Antietam (Maryland)
- Fredericksburg (Virginia)
- Chancellorsville (Virginia)
- Gettysburg (Pennsylvania)
- Bristoe Station (Virginia)
- Mine Run Operations (Virginia)
- Wilderness (Virginia)
- Po River (Virginia)
- Spotsylvania (Virginia)
- North Anna River (Virginia)
- Totopotomy (Virginia)
- Cold Harbor (Virginia)
- Petersburg (Virginia)
- Deep Bottom (Virginia)
- Reams’ Station (Virginia)
Casualties
Specific casualty figures for the 4th Ohio Infantry (Three Years’ Service) are not fully detailed in all primary sources. Fox’s Regimental Losses and the Official Records indicate the regiment sustained losses in killed, wounded, and by disease during its service, but exact numbers may vary by source.
Some details are incomplete in surviving primary sources.
Field Officers & Commanders
- Colonel Lorin Andrews
- Colonel John S. Mason
- Colonel James H. Godman
- Lieutenant Colonel James Cantwell
- Lieutenant Colonel Leonard W. Carpenter
- Major George Weaver
- Major Gordon A. Stewart
Regimental Roster
The full roster of the 4th Ohio Infantry (Three Years’ Service), including officers and enlisted men, is available for genealogical and historical research. The roster provides names, ranks, and service details for those who served in the regiment during its three-year term.
To view the complete roster, visit the 4th Ohio Infantry (Three Years’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, Volumes 5, 12, 19, 25, 27, 29, 36, 40, 42 (various parts and pages)
- Ohio Roster Commission, “Official Roster of the Soldiers of the State of Ohio in the War of the Rebellion”
- 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 2