When the Civil War began, Minnesota's population numbered about 172,000. Of these, an estimated 15% were mustered into military service to fight for the Union army. The National Archives Index shows 30,972 names. The actual number of men who served is placed at 26,717.
Two battles were fought in Minnesota during the war. These involved the Sioux Indians angered by the failure of the Federal government to provide annuities and by the poor quality of rations.