The regiment was initially equipped with smoothbore .69 caliber muskets converted from flintlock to percussion; in early 1862, they were replaced with Austrian Lorenz rifles.

The regiment saw its first action at Second Bull Run, followed by severe and bloody fighting in the Maryland Campaign which produced a combined casualty list of 323.

The Badgers would suffer heavily during the battle, out of 370 effective men, 194 would not return after July 3.

In the spring of 1864, the regiment signed up for another three years of service and thence fought in the Overland Campaign and the Siege of Petersburg.

[1] The regiment participated in the Grand Review of the Armies on May 23, 1865, and then mustered out at Louisville, Kentucky, on July 2, 1865.