The Averell Family Papers consist primarily of the personal, business, and legal papers of William Holt Averell of Cooperstown, New York. The collection also includes a substantial number of papers relating to or written by James Averell, Jr., William Holt Averell's father. In addition, the collection includes papers relating to other members of the Averell family and genealogical information regarding the Averell, Carter, Slayton, and Waldby families. The date range is mostly from 1790 to 1880.