The 43rd Ohio Infantry Regiment was organized in Mount Vernon, Ohio September 28, 1861, through February 1, 1862, and mustered in for three years service under the command of Colonel Joseph L. Kirby Smith.
The regiment was attached to 1st Brigade, 1st Division, Army of the Mississippi, to March 1862.
1st Brigade, 8th Division, Left Wing, XIII Corps, Department of the Tennessee, to December 1862.
4th Brigade, District of Corinth, Mississippi, 2nd Division, XVI Corps, to May 1863.
3rd Brigade, District of Memphis, Tennessee, 5th Division, XVI Corps, to November 1863.
Fuller's Brigade, 2nd Division, XVI Corps, to March 1864.
The 43rd Ohio Infantry mustered out of service at Louisville, Kentucky, on July 13, 1865.
10, Mississippi River, and capture of McCall's forces at Tiptonville, Mo., March 15-April 8.
Grant's Central Mississippi Campaign November 2, 1862, to January 12, 1863.
Dodge's Expedition to northern Alabama April 15-May 8.
Operations on line of Pumpkin Vine Creek and battles about Dallas, New Hope Church, and Allatoona Hills May 25-June 5.
Operations about Marietta and against Kennesaw Mountain June 10-July 2.
Binnaker's Bridge, South Edisto River, February 9.
Orangeburg, North Edisto River, February 12–13.