12th Ohio Infantry – 3 Years Service ​in the American Civil War

Overview

The 12th Ohio Infantry (Three Years’ Service) was an infantry regiment raised in Ohio for service in the Union Army during the American Civil War. Organized at Camp Dennison between June 19 and June 29, 1861, the regiment served primarily in the Western Virginia and Eastern Theater campaigns. The unit was known for its early and sustained participation in key engagements in West Virginia, Maryland, and Virginia, and for its notable actions at South Mountain and Antietam.

This unit is distinct from the 12th Ohio Infantry (Three Months’ Service).

Organization & Service

The 12th Ohio Infantry (Three Years’ Service) was organized at Camp Dennison, Ohio, from June 19 to June 29, 1861, under the command of Colonels John W. Lowe and Carr B. White. The regiment departed for the Kanawha Valley on July 6, 1861, arriving at Point Pleasant on July 9. On July 17, it fought at Scary Creek, West Virginia, where it engaged Confederate forces for three hours before withdrawing after expending its ammunition. The regiment subsequently entered Charleston, West Virginia, and advanced to Gauley Bridge, capturing significant quantities of arms and ammunition.

Marching south through Weston, Sutton, and Summerville, the regiment reached Carnifex Ferry and participated in the battle there on September 10, 1861. The 12th Ohio remained active in the Kanawha Valley until August 15, 1862, when it was ordered to join the Army of the Potomac. On August 27, 1862, the regiment was heavily engaged at Bull Run Bridge, suffering significant casualties. In September, it advanced into Maryland, skirmished at Monocacy Bridge, and entered Frederick City. At the Battle of South Mountain on September 14, the regiment executed three bayonet charges, capturing battle flags, arms, and prisoners. Three days later, it fought at Antietam.

After wintering in West Virginia, the regiment helped repel an attack at Fayette Court House. In 1864, it participated in the battle at Cloyd’s Mountain and later in the engagement at Lynchburg, Virginia. The 12th Ohio Infantry (Three Years’ Service) was mustered out at Columbus, Ohio, on July 11, 1864.

Engagements & Campaigns

• Scary Creek, West Virginia (July 17, 1861)
• Occupation of Charleston, West Virginia
• Gauley Bridge, West Virginia
• Carnifex Ferry (September 10, 1861)
• Bull Run Bridge (August 27, 1862)
• Monocacy Bridge, Maryland
• South Mountain (September 14, 1862)
• Antietam (September 17, 1862)
• Fayette Court House, West Virginia
• Cloyd’s Mountain (May 9, 1864)
• Lynchburg, Virginia

Casualties

• Scary Creek: 5 killed, 30 wounded, 4 missing
• Carnifex Ferry: 2 killed, 10 wounded
• Bull Run Bridge: 9 killed, 68 wounded (6 mortally), 12 missing
• South Mountain: 16 killed, 91 wounded, 8 missing
• Antietam: 6 killed, 29 wounded
• Fayette Court House: 2 killed, 9 wounded, 8 missing
• Cloyd’s Mountain: 11 killed, 68 wounded, 20 captured while tending wounded

Some details are incomplete in surviving primary sources regarding total losses for the entire service term.

Field Officers & Commanders

• Colonel John W. Lowe
• Colonel Carr B. White
• Lieutenant Colonel Jonathan D. Hines
• Major James D. Wallace
• Major Edward M. Carey

Regimental Roster

The full roster of the 12th Ohio Infantry (Three Years’ Service), including officers and enlisted men, is available for genealogical and historical research. For a complete listing of soldiers who served in this regiment, please visit the dedicated roster page.

View the 12th Ohio Infantry (Three Years’ Service) Roster.

Sources & References

• Official Records of the Union and Confederate Armies, Series I, Volumes 5, 9, 12, 19, 27, 37
• 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