September 12: Killing of Dakota Territorial Secretary
Perhaps the most violent moment in Dakota territorial politics was the killing of the territorial secretary in 1873. General Edwin Stanton McCook was a distinguished Civil War veteran and one of the “Fighting McCooks,” a prominent Union military family. In February of 1872, President Grant appointed McCook as secretary of Dakota Territory, a position which also served as acting governor. McCook soon afterward arrived in the capital city of Yankton with his family.
Source: prairiepublic.org