Col. Wm. M. Stone rendezvoused at Iowa City in Aug. 1862, and was mustered into service 9 Sep 1862. Moved to Davenport on the 14th, and thence to St. Louis. On the 22nd, moved to Rolla, and thence to Iron Mountain, arriving 26 Feb.March 9th, moved to St. Genevieve, MO; 22nd, took transports for Milliken's Bend. Apr 12th, moved to Richmond, LA, thence to Perkins' Landing.

The Twenty-second, belonging to the Thirteenth Corps, participated in its movements in the vicinity of Vicksburg. Was hotly engaged at Thompson's Hill, completely routing the enemy. Was in battle of Champion Hills, and various small encounters with the enemy, ending in a general charge of the brigade to break the enemy's line, resulting in the wounding of Col. Stone and loss of 164 officers and men.

After Col. Stone's fall, Col. Graham entered the rifle pits, but, on account of not having scaling ladders, only a few entered the fort; captured a few prisoners, but pits being commanded by guns from other position, they were untenable. Then commenced the siege and evacuation of Vicksburg.

Was on Sherman's campaign to Jackson. 13th Aug embarked on transports for Carrollton, LA. 4th Sept. proceeded to Algiers; thence to Brashear City, and camped near the ruins of the town of Berwick. Moved by steamer to mouth of the Rio Grande. A portion of the regiment was defeated by Texas Rangers. Bank's expedition up Red Riverproving a failure, the Twenty-second moved to New Orleans by steamer, and moved up Red River. The Twenty-second was then assigned to the 19th Corps, and moved by steamer to Fortress Monroe, arriving 24th July, and proceeded up James River and joined the forces under gen. Butler. On the 31st, were ordered to Washington, arriving Aug. 1st.

Aug. 2nd, marched into Maryland and camped on Georgetown Heights. On the 14th , marched and joined Gen. Sheridan in Shenandoah Valley, just in time to join in retreat; pursued to Early, and when the rebels were turned back, and were so severely defeated at Winchester, the Twenty-second behaved heroically, but losing many valuable officers and men; loss, 109. Participated in pursuit of Early and in several attacks on him and the capture of part of his army. The Twenty-second lost heavily at Winchester, Fisher's Hill and Cedar Creek. Until end of service the Twenty-second was constantly on the move. Mustered out at Savannah, GA 25 Jul 1865.