Abstract: Papers of Cadwallader Colden Washburn, a Wisconsin businessman; Congressman, 1855-1861, 1867-1871; Civil War officer; and governor, 1871-1874; consisting largely of personal letters from various members of his family, especially Elihu B. Washburne, a brother. The correspondence relates to the land and collection agency and law business of the firm of Washburn and Woodman at Mineral Point, Wisconsin, the lead shot manufacturing interests of the firm at Helena, Wisconsin, and the establishment of the Bank of Hallowell, in Maine. Also included are miscellaneous business papers of the Washburn-Crosby Company mills and the genealogical research of Jeannette (Washburn) Kelsey.