Companies A, B, C, D, E, F, and H moved to Cincinnati, May 20 and were engaged in guard and patrol duty in and about that city until July 18.
Moved to Cumberland, Maryland, July 28 and assigned to General Kelly's Command, Department of West Virginia.
Shipped to the Eastern Theater, they were designed to be placed in "safe" rear areas to protect railroads and supply points, thereby freeing regular troops for Lt. Gen. Ulysses S. Grant’s push on the Confederate capital of Richmond, Virginia.
Ohio Guard units met the battle-tested foe head on and helped blunt the Confederate offensive thereby saving Washington, D.C. from capture.
Ohio National Guard units participated in the battles of Monacacy, Fort Stevens, Harpers Ferry, and in the siege of Petersburg.