After the term of service was over in August, a number of the men re-enlisted for 3-years in the reconstituted 2nd Ohio Infantry, under the command of Colonel Leonard A. Harris in the brigade of William "Bull" Nelson.

It served in a number of posts in Kentucky, including Louisville, through February 1862, when it was part of the army's advance on Confederate-held Bowling Green and Nashville.

After guarding the Memphis and Charleston Railroad much of the summer, the 2nd Ohio marched back to Louisville in August and September in pursuit of the Confederate army of Braxton Bragg, eventually fighting at the Battle of Perryville on October 8 before returning to Nashville for most of the rest of the year.

The regiment, reassigned to the 1st Brigade, 1st Division, XIV Corps, Army of the Cumberland, saw more hard action at the Battle of Stones River in late December and early January.

[3] As Ulysses S. Grant's army pursued the retiring Confederates into Georgia in late November through May 1864, the regiment saw action at a number of small battles, including Ringgold, Dalton, Tunnel Hill, Buzzard's Roost Gap and Rocky Faced Ridge.

It remained in the siege lines around Atlanta until August 1, when the much depleted regiment was ordered to the rear at Chattanooga as the term of enlistment neared expiration.

[1] Colonel McCook stayed in the army as a brigade commander, ending the war with the rank of brigadier general.