Gabriel Manigault (1758-1809) was a Charleston merchant, plantation owner, architect, and South Carolina state Representative. In 1805, Manigault sold part of his property in South Carolina and moved to Clifton, an estate near Philadelphia, Pennsylvania. These are copies of Manigault's letters relating to members of the du Pont family.

Lehigh Coal Mine Company was an unincorporated joint-stock company, established in 1792, with the intention of developing a deposit of anthracite coal discovered by Jacob Weiss (1750-1839) and others at what is now Summit Hill in Carbon County, Pennsylvania. The collection consists of documents relating to land ownership and governance of Lehigh Coal Mine Company.

Pierre Samuel du Pont de Nemours (1739-1817) was a French political economist, writer, publisher, and public administrator. He was an advocate for a national educational system and promoted Franco-American trade relations. The collection consists of Pierre Samuel du Pont de Nemours correspondence and writings in addition to correspondence of his second wife, Françoise (Robin) Poivre.

Victor Marie du Pont (1767-1827) was a French diplomat who later immigrated to the United States and established various trading companies before moving to Delaware. He was the eldest son of Pierre Samuel du Pont de Nemours (1739-1817). The collection consists of correspondence, business and personal papers, and writings of Victor Marie du Pont and his wife, Gabrielle Joséphine (de la Fite de Pelleport) du Pont.