The collection contains information on Fox family speculation in western lands, two manuscript maps from the 1790's and 1830's depicting the family's holdings in northwestern Pennsylvania, and a photograph album from the 1890's documenting Chestnutwold, the Fox estate adjacent to Andalusia. Chief correspondents are Samuel and George Fox.

A Sachem and Civil War adjutant to Ulysses Grant, Ely Samuel Parker was an important figure in the Seneca Indian nation during the first half of the nineteenth century. Trained as an engineer, Parker was deeply involved in the Senecas' land disputes with the Ogden Land Company and he played an important role in interpreting Seneca culture for a white audience, most notably as a consultant for Lewis Henry Morgan. Collected by Arthur C. Parker, the Ely Samuel Parker Papers include correspondence, manuscripts, and printed materials relating primarily to Seneca affairs, history, language, and culture, as well as politics, education, engineering, and the Civil War. Among Parker's correspondents were Henry Clay, Millard Fillmore, Henry M. Flagler, Lewis Henry Morgan, Henry Rowe Schoolcraft, Daniel Webster, and Asher Wright. Several letters relate to Parker's service as engineer of public buildings in Galena, Illinois, and to his Masonic activities. Among the noteworthy items in the collection are several essays on Seneca history and culture, a fragment of Parker's diary, 1847, and a significant quantity of material on the Seneca language assembled by Asher Wright.