The Wadsworth Collections concern the first and continued settlement of land in the Genesee region known as the Phelps and Gorham Purchase. The collections consist of approximately 50,000 items from the land offices of the two branches of the Wadsworth family of Geneseo and cover the years 1790 to about 1950, with most dating from the 19th century. Business correspondence and ledgers, vouchers, deeds, maps and other business-related materials make up most of the collections.
The Library's collection does not include official papers from the terms of Congressman James W. Wadsworth (1846-1926) or U.S. Senator James. W. Wadsworth, Jr. (1877-1952). The Library of Congress is home to The James Wadsworth Family Papers, a collection of personal and business materials which includes a large portion dealing with the Senator.