Overview
The 1st Ohio Infantry (Three Months’ Service) was an infantry regiment organized in Ohio for Union service at the outset of the Civil War. The regiment was formed at Columbus on April 18, 1861, in direct response to President Lincoln’s call for 75,000 volunteers. Comprised largely of pre-war militia companies from across the state, the unit was among the earliest Ohio regiments to enter federal service. It served in the Eastern Theater and participated in some of the first engagements of the war.
This unit is distinct from the 1st Ohio Infantry (Three Years’ Service).
Organization & Service
The 1st Ohio Infantry (Three Months’ Service) was organized at Columbus, Ohio, on April 18, 1861. The regiment consisted of companies drawn from various Ohio cities: Company A (Lancaster Guards), B (Lafayette Guards), C (Dayton Light Guards), D (Montgomery Guards of Dayton), E (Cleveland Grays), F (Hibernian Guards of Cleveland), G (Portsmouth Guards), H (Zanesville Guards), I (Mansfield Guards), and K (Jackson Guards of Hamilton). Many of these companies were established militia units prior to the war.
The regiment departed Columbus for Washington, D.C., on April 19, 1861, and was mustered into United States service at Lancaster, Pennsylvania, on April 29, 1861. Upon arrival in Washington in early May, the 1st Ohio was assigned to General Schenck’s brigade within General Tyler’s division. The regiment participated in the action at Vienna, Virginia, and later fought in the First Battle of Bull Run. After completing its three-month term, the regiment was mustered out of service between August 1 and August 16, 1861.
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
- Action at Vienna, Virginia (June 17, 1861)
- First Battle of Bull Run, Virginia (July 21, 1861)
Casualties
- Vienna, Va.: 9 killed, 2 wounded
- First Bull Run: 3 killed, 2 wounded, 2 missing
Total losses for the regiment during its three months’ service are not fully detailed in all sources.
Field Officers & Commanders
- Colonel Alexander McDowell McCook
- Lieutenant Colonel Edwin A. Parrot
- Major John G. Hughes
Regimental Roster
The full roster of the 1st Ohio Infantry (Three Months’ 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 research.
To view the complete roster, visit the 1st Ohio Infantry (Three Months’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, Vol. 2
- Ohio Roster Commission, Official Roster of the Soldiers of the State of Ohio in the War of the Rebellion, Vol. 1
- 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. 2