Abstract: Papers of an early La Crosse, Wisconsin, banker and mayor, and of his family. Gysbert van Steenwyk, Sr. (1814-1902), who founded the Batavian Bank in La Crosse, Wisconsin, and was active in state and local politics. Van Steenwyk, a Dutch immigrant, served a term in 1873 as mayor of La Crosse, Wisconsin, and also served in the Wisconsin state legislature as assemblyman in 1859 and senator 1879-1880. Other family members represented in the collection include Mariette Nichols van Steenwyk, their son, Gysbert van Steenwyk, Jr., banker and businessman of La Crosse, Wisconsin; the son's wife Grace Pettinhill Hogan van Steenwyk; and Ella May van Steenwyk Cassels, daughter of Gysbert Sr. and Mariette van Steenwyk.

The collection includes personal and business correspondence together with business and organization financial records, legal documents and genealogical information, papers and records relating to the estate of Cadwallader C. Washburn and miscellaneous materials. Among the business interests of his son Gysbert van Steenwyk, Jr., were the La Crosse Trust Co., Machine Products Co., La Crosse Rubber Mills, and La Crosse Floral Co. Apart from their business activities, the van Steenwyks were involved with the La Crosse Theater Co., and the Home for the Friendless. Some materials are in the Dutch language.