Organization 

The Twenty-First Wisconsin Infantry Regiment (21st Wisconsin Infantry Regiment) organized at Camp Bragg, Oshkosh, Wisconsin, and mustered into the service of the United States on September 5, 1862.  They left the state on September 11. Then, they proceeded to Covington, KY, and then went to Louisville. 

Active Duty 

In Louisville, they joined the same brigade as the First Wisconsin Infantry Regiment. In that brigade, they served in the division/corps with the First and Tenth Wisconsin Infantry Regiments. That organization of the Union forces was known as the Army of the Cumberland. The 21st would serve with them until the conclusion of the Atlanta Campaign. 

In October 1864, the time of enlistment of the First and Tenth Infantry expired. The members of each of those organizations whose terms had not expired were transferred to the 21st Infantry, while the First and Tenth mustered out of the service. 

After the Atlanta Campaign, the 21st served in various campaigns in Kentucky, Tennessee, and northern Alabama. These campaigns included battles such as the battle of Perryville (Chaplin Hills) October 8, 1862, and the battle of Stones River (or Murfreesboro) December 30 – January 1, 1863. They also fought in the Tullahoma Campaign from June 23 to July 7. In the fall they engaged in the battle of Chickamauga from September 19 to 21. Later, they participated in the battle of Missionary Ridge on November 25, 1863. 

On May 3, 1864, having joined Shermans Army, the 21st Infantry participated in movements to Ringgold, GA, and Buzzard Roost. They engaged at the battle of Resaca on May 15, Kennesaw Mountain from June 10 to July 3, Peachtree Creek on July 20, the battle of Atlanta from July 21 to 22, and the battle of Jonesborough on September 1, 1864. 

On November 15, they rejoined Shermans Army. With them, they participated in the "March to Sea", in operations around Savannah, GA, until the surrender of that place on December 21, 1864. On January 20, 1865, with the Fourteenth Army Corps, the 21st left Savannah. Then, they participated in the campaign of the Carolinas from January 1 to April 26.  

After the surrender of the Confederates under Johnston on April 26, 1865, the 21st marched to Washington. In Washington, they took part in the Grand Review and going into camp near there until June 8, 1865, when the regiment was mustered out of service.  They returned to Milwaukee and disbanded June 17, 1865. 

Casualties 

The 21st Infantry lost 5 officers and 117 men to mortal wounds and an additional 3 officers and 180 men to disease. 

For Further Research

Search our collections for photos and artifacts from Wisconsin in the Civil War. Read about other Wisconsin Civil War regiments. For detailed regimental histories of the U.S. Civil War, consult the Frederick H. Dyer, Compendium of the War of the Rebellion: Regimental Histories.

The histories above, unless otherwise noted, are adopted from Charles E. Estabrook, ed., Records and Sketches of Military Organizations, (Madison, 1914).