The four Companies of the Regiment were organized in the spring of 1865, when the government ordered all recruits not mustered in to be discharged.

They were sent to St. Louis, Missouri and then to Leavenworth, Kansas where they were transferred to the 51st Infantry 10 June 1865 by order of the War Department.

Company A became Company G of the 51st; Company B became Company H; Company C became K; and Company O became I.

They were mustered out with 51st Regiment in August 1865.

The original strength of the four companies was 380. Gained by recruits, 9; total, 389.

Loss by death, 8; desertion, 14; discharge, 47; mustered out, 315.