This regiment was composed of companies raised in Linn, Black Hawk, Jones, Jackson, and Cedar counties. It had 970 men and its field officers were: Colonel, William Smyth; lieutenant-colonel, J. W. Jenkins; major, Ezekiel Cutler. It went into camp at Davenport in October, and early in November sailed for Helena, Ark. It soon after joined Sherman's army operating against Vicksburg, and was in the battle of Chickasaw Bayou. In January, 1863, it was in the expedition which was sent against Arkansas Post, and took part in the battle at that place. It was in the battle of Raymond May 12th, and was in the army that captured Jackson. In the siege and capture of Vicksburg it rendered good service, fighting bravely in the assault of May 22d, where Lieutenant-Colonel Jenkins was wounded. After the fall of Vicksburg it was in the army sent to Chattanooga and participated in the battles of Lookout Mountain, Missionary Ridge, and Ringgold, losing many men. In May, 1864, the regiment marched to northern Georgia and made a part of the grand army, 100,000 strong, under General Sherman, then marching towards the sea. Gen. J. E. Johnston was in command of the confederate army of about 50,000 gathered to resist the invasion.
Johnston's army had taken a position near Dalton on a spur of the mountains. At Resaca, fifteen miles south, the hostile armies came into collision on the 12th of May. The battle raged fiercely for several days, as one after another of the strong positions were carried by the union army. Lieutenant-Colonel Jenkins was again wounded in these battles. On the 28th a severe battle was fought at Dallas and several other sharp engagements followed. But the union army continued to advance, and Atlanta was finally taken. On the 15th of November Sherman's army again started on its march to the sea. In the battles which had taken place the Thirty-first had lost many men, always doing good service. Colonel Smyth resigned in December and was succeeded by Lieutenant-Colonel Jenkins, who was an excellent officer. In the march through the Carolinas the Thirty-first was engaged in several fights with the enemy and did good service at the battle of Bentonville. It reached Washington in May and was at the grand review of the 24th. It was disbanded at Davenport, where it received a great ovation from the citizens. From nearly 1,000 men who marched with it to the war, but 370 remained when it was mustered out. Disease, hardships, and battles had thus reduced its numbers.
SOURCE, Benjamin F. Gue, Biographies And Portraits Of The Progressive Men Of Iowa, Volume 1, p. 112