This regiment was raised in northeastern Iowa in August and September, 1861, and was organized in Dubuque by Hon. William Vandever, Member of Congress, who was specially commissioned by the President to raise a regiment in his District. He was made Colonel.
The Ninth Iowa proceeded to Benton Barracks, at St. Louis, with 977 men.

From October until January, 1862, the regiment was stationed about Franklin, Mo., for the purpose of guarding railroads. Here they found a most unhealthy region and inclement weather, which, in three months, had reduced their number by death and discharge, some twenty-four men. This loss was more than made up by additional enlistments.

The regiment, on the 7th of March, experienced its maiden fight in thebattle of Pea Ridge. Its first experience was a severe one, and while victory crowned the Union side, it was with severe loss and the cost of many brave men. Capt. Drips, of Jackson County, was killed while leading his men on a gallant charge. His loss was deeply felt. He had been a soldier in the Mexican war, and was not only a highly respected leader, but a brave and gallant soldier. Out of 560 men of the Ninth Iowa engaged in the fight, 237 were killed or wounded, and 3 captured.

A march of 600 miles on a campaign through Missouri and Arkansas brought the regiment to Helena July 17, 1862, where the regiment was in camp for five months, and had its only experience during the service, in regular camp drill and thorough discipline. Here the regiment received a stand of silk colors from a committee of ladies in Boston, Mass., in honor of their heroic service at Pea Ridge. A couple of days at Vicksburg the regiment was under fire, and, December 31, 1862, formed the Ninth Iowa on Yazoo River.

After assisting at the capture of Arkansas Post, January 11, 1863, the regiment proceeded to Young's Point, La., where, during the months of February and March, in a sickly climate, disease brought to the regiment all the evils of the battle-field, and left none of its honors. Assisting at the capture of Jackson May 14, on May 22, in line with the whole Army of the Tennessee,
the regiment went first up to the grand assault upon Vicksburg. In a few terrible moments, the command lost 79 in killed or wounded. The entire loss in the siege to the Ninth Iowa was 121 men.

The regiment engaged in various campaigns and marches through Mississippi, Arkansas, Tennessee and Alabama, pitching their tents at the foot of Lookout Mountain November 23, just in time to take part in the battle above the clouds. The close of 1863, found the regiment reduced in number 510 men.

January 1, 1864, was celebrated by the re-enlistment of 287 veterans of the regiment for another term of three years. This entitled them to a thirty days' furlough, and February 14, found them at Dubuque. Returning with 125 three-year recruits, the regiment was soon in active service. Before the 8th of September, it had been honorably engaged in the battles of Resaca, Dallas, New Hope, Big Shanty, Kenesaw Mountain, Chattahoochie River, Decatur, Atlanta, Jonesboro and Lovejoy. The losses were small compared with some of its previous encounters, being only 90 in killed, wounded and prisoners. The non-veterans mustered out September 23, 1864.

The regiment was in the famous " march to the sea," and fought its last battle at Bentonville. The Ninth Iowa was present in the military pageant May 24, which consisted in the review of Sherman's army in the streets of Washington.

July 18, 1865, the Ninth Iowa mustered out at Louisville, numbering 594.  The regiment marched over 4,000 miles, and traveled by steamer and railroad some 6,000 more. The losses during service were, killed, 117; died of disease, 200; discharged for disability, 243, or a total list of 560 casualties.