Eleutherian Mills is the house built by Eleuthère Irénée du Pont (1771-1834), above his gunpowder mills, the E.I. du Pont de Nemours & Company. It served as a home to the du Pont family for generations, the last being Louise du Pont Crowninshield (1877-1958). The collection contains material related to the restoration of the home prior to Crowninshield occupying it. Also included are materials related to a road to the Eleutherian Mills and Nemours residences, repairs to the iron bridge across the Brandywine, and description of E.I. du Pont's garden.

Kim Burdick is a public historian, preservationist and former advisor to the National Trust for Historic Preservation. Louise du Pont Crowninshield (1877-1958) was an early leader in the field of historic preservation. The collection includes photocopies of all known surviving Crowninshield letters and Burdick's notes.

Louise du Pont Crowninshield (1877-1958) was an early leader in the field of historic preservation and a collector of antiques and hooked rugs. This collection includes two letters addressed to Nell (McCall) Pringle (1879-1937), of Charleston, South Carolina.

Louise du Pont Crowninshield (1877-1958) was an early leader in the field of historic preservation and a collector of antiques and hooked rugs. The collection includes her papers as well as those of her husband Francis Boardman Crowninshield, her mother, and other family members.

Louise Evelina du Pont (1877-1958) was an heiress and preservationist, who was the great granddaughter of Eleuthère Irénée du Pont (1771–1834), the founder of E. I. du Pont de Nemours and Company. She was the last du Pont to live on the Eleutherian Mills estate. This collection consists of photographic and graphic materials primarily of Crowninshield's extended du Pont family and friends. The collection has been organized into four series: Family portraits, Travel photographs, Residences, and Mary Pauline Foster du Pont sketches and collection of travel souveniers.

P.S. du Pont (1870-1954) and Louise du Pont Crowninshield (1877-1958) were second counsins and both had an interest in preservation. In the letter, du Pont suggests Eleutherian Mills and Hagley property be preserved as a historic site.

Victorine du Pont Foster (1849-1934) was the granddaughter of Eleuthère Irénée "E.I." du Pont (1771-1834) who founded the E.I. du Pont de Nemours & Company, a chemical company which began with the production of gunpowder. Her husband was Antoine Foster (1847-1928). The collection contains a typescript of Foster's memoir, "A Lost Garden" which describes the former garden at Eleutherian Mills.

Walt Biddle (1925-1995) was a gardener in the household of Louise du Pont Crowninshield (1877-1958) and Francis B. Crowninshield (1869-1950) at Eleutherian Mills in Greenville, Delaware. In his oral history interview transcript, Biddle describes the Crowninshields and life at Eleutherian Mills in the 1940s and 1950s.