This famous regiment was organized June 5, 1861, and ordered into quarters at Benton Barracks near St. Louis about the middle of October in the same year.

The middle and western portion of Missouri was the highway to the so-called Southern Confederacy for recruits, sympathizers and bushwhackers, and during the entire winter of 1861, eight companies of the regiment were engaged in patrolling this region.

In July the notorious guerrilla chief Quantrill was encountered by a few companies of the 1st cavalry on the wooded cliffs of Big Creek in Cass County.

In December the 1st took part in an important expedition to Van Buren, Ark., resulting in a defeat of some Confederates and the capture of immense stores.

[1] In Jan., 1864, 500 of the regiment reenlisted and on March 23, waiving their right to a veteran furlough at that time, joined the 7th Army Corps and took a prominent part in all the operations of the Camden Expedition.

The fight lasted for six hours, when Brig-Gen. Rice ordered up the dismounted men of the regiment to deploy as skirmishers, and the enemy, stubbornly contesting the ground, was driven back through the city of Camden on the evening of the same day.

On January 14, 1865, a detachment of the 1st IA and other regiments, was ordered by boat about 100 miles up the Arkansas river to Dardanelle, at which place they engaged a Confederate force of 1,600 men under Gen. Cooper, killing and wounding 90.

By Feb. 17 the regiment had gone to Memphis, in the vicinity of which city it remained, scouting occasionally, till June 15, when Gen. Grant ordered the command to march from Alexandria, La., to Texas.