21st Regiment, Missouri Infantry (Union)

Organized February 1, 1862, from 1st and 2nd Northeast Regiments Missouri Infantry. Attached to Dept. of Missouri to March, 1862. 1st Brigade, 6th Division, Army of the Tennessee, to July, 1862. 1st Brigade, 6th Division, District of Corinth, Miss., to November, 1862. 1st Brigade, 6th Division, Left Wing 13th Army Corps (Old), Dept. of the Tennessee, to December, 1862. District of Columbus, Ky., 16th Army Corps, Dept. of the Tennessee, to May, 1863. 4th Brigade, District of Memphis, Tenn., 5th Division, 16th Army Corps, to January, 1864. 1st Brigade, 3rd Division, 16th Army Corps, to December, 1864. 1st Brigade, 2nd Division, Detachment Army of the Tennessee, Dept. of the Cumberland, to February, 1865. 1st Brigade, 2nd Division, 16th Army Corps (New), Military Division West Mississippi, to August, 1865. Dept. of Alabama to April, 1866.