The regiment fought at Shiloh, Corinth, and Stones River.
In April 1863 the unit acquired horses and Spencer rifles and became mounted infantry,[1] serving in the Tullahoma campaign and at Chickamauga.
The regiment was attached to Wood's Brigade, McCook's Command, Army of the Ohio, October–November 1861.
1st Brigade, 2nd Division, Right Wing, XIV Corps, Army of the Cumberland, to January 1863.
The 39th fought in this brigade (even after conversion to mounted infabtry) in the battles of Shiloh, Stones River, Liberty Gap, Chickamauga, to October 1863.
Ordered to Kentucky and duty at Muldraugh's Hill, Camp Nevin, Nolin Creek, and Green River until February 1862.
Buell's Campaign in northern Alabama and middle Tennessee June to August.
March to Nashville, Tennessee, then to Louisville, Kentucky, in pursuit of Bragg August 20-September 26.
March to Bowling Green, Kentucky, then to Nashville, Tenn., October 16-November 7, and duty there until December 26.
Passage of Cumberland Mountains and Tennessee River and Chickamauga Campaign August 16-September 22.