Company A of the 12th Kentucky Infantry Regiment was organized at Camp Dick Robinson on September 26, 1861, while the remaining nine companies were organized near Waitsboro, Kentucky, from December 1861 through January 1862 and mustered at Clio, Kentucky, in January 1862 for a three-year enlistment.
The regiment was attached to Thomas' Command, Camp Dick Robinson, Kentucky, to November 1861.
1st Brigade, 1st Division, III Corps, Army of the Ohio, to November 1862.
1st Brigade, 3rd Division, Center, XIV Corps, Army of the Cumberland, to December 1862.
District of Western Kentucky, Department of the Ohio, to June 1863.
1st Brigade, 2nd Division, XXIII Corps, Army of the Ohio, to August 1863.
1st Brigade, 3rd Division, XXIII Corps, Army of the Ohio, to February 1865, and Department of North Carolina to July 1865.
The 12th Kentucky Infantry mustered out of service on July 11, 1865.
Actions at Albany and Travisville, Ky., September 29, 1861 (Company A).
Operations in Wayne and Clinton Counties and at Mill Springs, Ky., November 1861.
Buell's Campaign in northern Alabama and middle Tennessee June to August.
March to Nashville, Tenn.; thence to Louisville, Ky., in pursuit of Bragg, August 20-September 25.
Moved to Camp Nelson and Danville and Join Gen. Burnside.
Burnside's march over Cumberland Mountains and Campaign in eastern Tennessee August 16-October 17.
Watauga River, Blue Springs, October 10.
Battles about Dallas, New Hope Church and Allatoona Hills May 25-June 5.
Pursuit of Hood to the Tennessee River December 17–28.