It was assigned to Abercrombie's 6th Brigade of Negley's 2nd Division, Patterson's Army.

The regiment was reorganized with new 3-year enlistees by Colonel Starkweather at Milwaukee and was mustered into federal service on October 19, 1861.

The 1st Wisconsin Infantry initially mustered 810 men and added no recruits.

[2] One of the fatalities was Second Sergeant of Company B, Warren M Graham, 18 years old, of Milwaukee, Wisconsin.

[5] The regiment suffered 6 officers and 151 enlisted men killed in action or who later died of their wounds, plus another 1 officer and 142 enlisted men who died of disease, for a total of 300 fatalities.