Harmen Harmanse was the patriarch of the Gansevoort family in Albany, New York, arriving in the area by 1657. Although not the first Ten Eyck in America, Jacob C. Ten Eyck was the first to come to Albany, moving from Manhattan after 1654. The two families intermarried several times over the years, along with other Dutch families in the area. This collection includes correspondence, financial records, estate records, and other family-related information.

Papers and records of the Ten Eyck and Ten Broeck families, business records of Johannes Beekman, business and political correspondence of Leonard Gansevoort and business records of Cuyler-Gansevoort firm as well as other records relating to the military, land transactions, the Watervliet Turnpike Company and other topics.