Longwood Gardens is a series of formal display gardens in Kennett Square, Pennsylvania, that was developed by Pierre S. du Pont (1870-1954) after he purchased the site from the Peirce family in 1906. The collection is comprised of two oral history interview projects. The first is with Eddie Dowling (1889-1976), an actor, screenwriter, playwright, director, producer, songwriter, and composer. The second project is commissioned oral histories with people with remembrances of du Pont and the development of Longwood Gardens.

Irene Sophie du Pont (1877-1961) was a philanthropist who served as the chairperson of the Delaware Commission for the Blind for thirty years. She married her distant cousin, Irénée du Pont (1876-1963), on February 1, 1900. Their eldest daughter was Irene "Sophie" Sophie du Pont May (1900-2001). Sophie du Pont May was a churchwoman and a philanthropist. This small collection consists of two sets of papers, one belonging to Irene Sophie du Pont and the other to her daughter, Sophie du Pont May. The papers were removed from each of their respective lap writing desks for preservation purposes. Irene Sophie du Pont's papers consist primarily of letters written to her between 1887 and 1898, prior to her marriage in 1900. Sophie du Pont May's papers are entirely comprised of her school materials from the Friends School in Wilmington, Delaware, dating from 1910 to 1916.

Marie Delphine du Pont (1916-2009) was the great-great-grandaughter of E.I. du Pont (1771-1834), the founder of the DuPont Company. Her papers consist of letters and postcards between du Pont and her cousin, Irene Sophie du Pont May (1900-2001).

Irene "Sophie" Sophie du Pont May (1900-2001) was a churchwoman, a philanthropist, and a descendant of Pierre Samuel du Pont de Nemours (1739-1817) who founded the E.I. du Pont de Nemours & Company with his son Eleuthère Irénée du Pont (1771-1834) in 1802. The E.I. du Pont de Nemours & Company is a chemical company more commonly referred to as the DuPont company. The collection consists of Sophie du Pont May's family correspondence and financial correspondence as well as correspondence between her father Irénée du Pont (1876-1963) and his older sister Louisa d'Andelot du Pont Copeland (1868-1926).