Organized at St. Louis, Mo., as the "Washington Zouves" and mustered into Federal service as the 9th Missouri Volunteers, September 18, 1861 (Cos. "A," "B," "C" at Cape Girardeau from August 6, 1861).

Attached to Kelton's Brigade, Pope's Division, Fremont's Army of the West, to November, 1861.

(Designation of Regiment changed to 59th Illinois Infantry February 12, 1862.)

2nd Brigade, 3rd Division, Army of Southwest Missouri, to June, 1862.

30th Brigade, 9th Division, Army of the Ohio, to October, 1862.

30th Brigade, 9th Division, 3rd Corps, Army of the Ohio, to November, 1862.

The 59th Illinois Infantry was originally organized as the "Washington Zouaves" at the St. Louis Arsenal, and was intended to form a Missouri "Zouave Brigade" in association with the 8th Missouri Volunteer Infantry.

[2] However, it was subsequently organized and uniformed as a standard infantry regiment[3] and mustered into Federal service on September 18, 1861, as the 9th Missouri Volunteers.

While organized in St. Louis and originally mustered in as a Missouri regiment, the majority of soldiers were from the state of Illinois and the regiment was transferred to the control of the Adjutant General of Illinois on February 12, 1862, and redesignated the 59th Illinois Volunteer Infantry.

To LaMine Bridge December 23 and duty there till January 25, 1862.

Campaign against Sterling Price's forces in northern Arkansas February and March.

March to Murfreesboro, Tennessee, August 8-September 1, thence to Louisville, Ky., in pursuit of Braxton Bragg's army, September 3–26.

March to Nashville, Tennessee, October 17-November 7 and duty there till December 26.

Guard supply trains over Mountain in rear of Bragg's army during Battle of Chickamauga.

Battles of Taylor's Ridge and Ringgold Gap, November 27.

Operations on line of Pumpkin Vine Creek and battles about Dallas, New Hope Church and Allatoona Hills May 25-June 5.

Battle of Ruff's Station, Smyrna Camp Ground, July 4.

Pursuit of General John Bell Hood's army, into Alabama, October 3–26.

Moved to New Orleans, La., June 16, thence to Indianola, Texas, July 7.

The regiment suffered 4 officers and 105 enlisted men who were killed in action or mortally wounded and 4 officers and 117 enlisted men who died of disease, for a total of 230 fatalities.