_Army of the Cumberland_—Maj. Gen. William S. Rosecrans
_Fourteenth Army Corps_—Maj. Gen. George H. Thomas
1st Division—Brig. Gen. Absalom Baird
2d Division—Maj. Gen. James S. Negley
3d Division—Brig. Gen. John M. Brannan
4th Division—Maj. Gen. Joseph J. Reynolds
_Twentieth Army Corps_—Maj. Gen. Alexander McD. McCook
1st Division—Brig. Gen. Jefferson C. Davis
2d Division—Brig. Gen. Richard W. Johnson
3d Division—Maj. Gen. Philip H. Sheridan
_Twenty-first Army Corps_—Maj. Gen. Thomas L. Crittenden
1st Division—Brig. Gen. Thomas J. Wood
2d Division—Maj. Gen. John M. Palmer
3d Division—Brig. Gen. H. P. Van Cleve
_Reserve Corps_—Maj. Gen. Gordon Granger
1st Division—Brig. Gen. James B. Steedman
2d Division—Col. Daniel McCook
_Cavalry Corps_—Brig. Gen. Robert B. Mitchell
1st Division—Col. Edward M. McCook
2d Division—Brig. Gen. George Crook
[Illustration: _“The First Gun at Chickamauga.” Confederates open
fire on Union cavalry at Reed’s Bridge._ A. R. Waud wartime sketch.
From Brown, _The Mountain Campaign in Georgia_.]