Recruited from Tennessee Unionists, the regiment was organized in August 1861 and fought at Mill Springs in January 1862.
The regiment was dismounted and fought in the Atlanta campaign until it was withdrawn in August 1864.
Subsequently, it performed garrison duty in East Tennessee until August 1865.
The 1st Tennessee Infantry was organized at Camp Dick Robinson in Garrard County, Kentucky August through September 1861 and mustered in for a three-year enlistment.
The regiment was attached to Thomas' Command, Army of the Ohio, to November 1861.
3rd Brigade, District of West Virginia, Department of the Ohio, to November 1862.
1st Brigade, 2nd Division, Center, XIV Corps, Army of the Cumberland, to January 1863.
District of Central Kentucky, Department of the Ohio, to June 1863.
1st Brigade, 1st Division, XXIII Corps, Army of the Ohio, to August 1863.
2nd Brigade, 1st Division, Cavalry Corps, Department of the Ohio, to April 1864.
2nd Brigade, 4th Division, District of East Tennessee, to August 1865.
Skirmishes at Big Creek Gap and at Jacksboro March 14 (Company A).
Operations at Rogers' and Big Creek Gaps September 10.
Evacuation of Cumberland Gap and retreat to Greenupsburg, Ky., September 17-October 3.
Expedition to Monticello and operations in southeast Kentucky April 25-May 2.
Sanders' Raid on East Tennessee & Virginia Railroad and destruction of Slate Creek, Strawberry Plains and Mossy Creek bridges June 14–24.
Operations against Scott's forces in eastern Kentucky July 25-August 6.
Lancaster, Stanford and Pain's Lick Bridge July 31.
Operations on line of Pumpkin Vine Creek and battles about Dallas, New Hope Church and Allatoona Hills May 25-June 5.
Relieved August 11 and ordered to Knoxville, Tenn. Duty there and in eastern Tennessee until March 1865.
Expedition from Irish Bottom to Evans' Island January 25, 1865.
Ordered to Cumberland Gap March 16, 1865, and duty there until August.