The 15th Ohio Infantry Regiment was organized in Columbus, Ohio, on April 27, 1861, in response to President Lincoln's call for 75,000 volunteers and mustered into service on May 4, 1861. The regiment moved to Zanesville, Ohio, May 8, then to western Virginia. It performed duty on the Baltimore & Ohio Railroad and operations in the vicinity of Philippi, Laurel Hill and Carrick's Ford June 3-July 16. Involved in action at Bowman's Place June 29. Ordered back to Columbus and mustered out August 27–31, 1861.
Three-years regiment
The 15th Ohio Infantry was reorganized at Mansfield, Ohio, in September 1861 and mustered in for three years service under the command of Colonel Moses R. Dickey. The regiment was attached to McCook's Command, October to November 1861. 6th Brigade, Army of the Ohio, to December 1861. 6th Brigade, 2nd Division, Army of the Ohio, to September 1862. 6th Brigade, 2nd Division, I Corps, Army of the Ohio, to November 1862. 1st Brigade, 2nd Division, Right Wing, XIV Corps, Army of the Cumberland, to January 1863. 1st Brigade, 2nd Division, XX Corps, Army of the Cumberland, to October 1863. 1st Brigade, 3rd Division, IV Corps, to August 1865. Department of Texas to November 1865. The 15th Ohio Infantry mustered out of service at San Antonio, Texas, on November 21, 1865, and returned to Columbus where its members were discharged on December 27, 1865.
Detailed service
1861
Moved to Camp Dennison, Ohio, September 26, thence to Lexington, Ky., October 4.
Duty at Camp Nevin, Ky., October 14-December 9, 1861.
Occupation of Munfordville, Ky., December 10, 1861.
Duty at Bacon Creek, Ky., until February 14, 1862.
1862
Advance to Bowling Green, Ky., and Nashville, Tenn., February 14-March 2.
March to Savannah, Tenn., March 16-April 6.
Battle of Shiloh April 6–7.
Advance on and siege of Corinth, Miss., April 29-May 30.
March to Battle Creek, Ala., June 10-July 18, and duty there until August 20.
March to Louisville, Ky., in pursuit of Bragg, August 20-September 26.
Pursuit of Bragg into Kentucky October 1–15.
March to Nashville, Tenn., October 16-November 7, and duty there until December 26.
Advance on Murfreesboro, Tenn., December 26–30.
Battle of Stones River December 30–31, 1862 and January 1–3, 1863.
Operations against Hood in northern Georgia and northern Alabama September 29-November 3.
Nashville Campaign November–December. Columbia, Duck River, November 24–27.
Battle of Franklin November 30.
Battle of Nashville December 15–16.
Pursuit of Hood to the Tennessee River December 17–28.
1865
Camp at Bird Springs, Ala., until March 1865.
Operations in eastern Tennessee March 15-April 22.
At Nashville, Tenn., until June.
Moved to New Orleans, La., June 16, thence to Texas.
Duty at Green Lake until August 10, and at San Antonio until November.
Mustered out November 21, 1865.
Reach Columbus, Ohio, December 25, and discharged from service December 27, 1865.
Casualties
The regiment lost a total of 315 men during service; 7 officers and 172 enlisted men killed or mortally wounded, 1 officer and 135 enlisted men died of disease.