The 10th MO Infantry Regiment was originally organized as Steen's MO Inf Regt in northwest AR on 10 Nov 1862. As part of Parsons' MO Brigade it was engaged at the battle of Prairie Grove, AR on 7 Dec 1862 where it suffered substantial casualties, losing both Col. Alex. Early Steen and LTC William C. Chappell. It then moved to Little Rock. It attacked the Federal fortification at Helena, AR on 4 Jul 1863, and again suffered very heavy casualties, especially in prisoners. Following Helena the regiment was consolidated with elements of the 9th MO Infantry Regiment (White's)and was known temporarily as the 10th MO Infantry Regt (Consolidated). It fought at Pleasant Hill, LA on 9 Apr 1864 and at Jenkins' Ferry, AR on 30 Apr 1862. The regiment surrendered and was paroled at Shreveport, LA in Jun 1865.

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