The Dimmick family were descendants of the founders of E.I. du Pont de Nemours & Company, a chemical research and manufacturing company. The collection contains a microfilm copy of correspondence between Joanna (Smith) du Pont (1815-1876) and her daughter, Joanna (du Pont) Dimmick (1854-1901), and letters from Sophie M. du Pont (1810-1888) to her niece, Dimmick, and the latter's step-daughter, Lavinia Elizabeth Dimmick (1874-1946). The letters are personal in nature, including du Pont family news.

Eleuthère Irénée du Pont (1771-1834), founder of E.I. du Pont de Nemours & Co., and Sophie Madeleine Dalmas du Pont (1775-1828) had four daughters. This group of materials within the Winterthur Manuscripts collection contains the papers of the three eldest: Victorine (du Pont) Bauduy (1792-1861), Evelina (du Pont) Bidermann (1796-1863), and Eleuthera (du Pont) Smith (1806-1876), as well as their respective husbands: Ferdinand Bauduy (1791-1814), James Antoine Bidermann (1790-1865), and Thomas MacKie Smith (1809-1852). Victorine du Pont Bauduy and Eleuthera du Pont Smith were teachers at the Brandywine Manufacturers' Sunday School (BMSS), a nonsectarian school offering classes in reading, writing, arithmetic, and Bible lessons. Evelina du Pont Bidermann spent much of her adult life traveling alongside her husband and then building the Winterthur mansion in Delaware. Their papers document details about their education, social life, family, attitudes, and activities through incoming and outgoing correspondence, as well as personal papers such as diaries and account books.

Eleuthera du Pont Smith (1806-1876) and Sophie Madeleine du Pont (1810-1888) were daughters of Eleuthère Irénée du Pont (1771-1834) and Sophie Madeleine Dalmas du Pont (1775-1828). This collection contains letters from the du Ponts to Mary Wilkinson, a former student at the Brandywine Manufacturers' Sunday School. The letters discuss domestic matters, including family news, health, faith, and needlework for the mills.

Henry Belin du Pont (1898-1970) was a research engineer with General Motors and the vice president of E.I. du Pont de Nemours & Company from 1939 to 1963. This collection contains correspondence from several generations of the family from the early nineteenth through the twentieth century, including Francis Gurney Smith (1784-1873), Elizabeth (Eliza) MacKie Smith (1787-1861), Joanna Smith du Pont (1815-1876), Frances du Pont Coleman (1838-1902), Eleuthera "Ella" du Pont Bradford (1848-1906), Eleuthera Bradford du Pont (1873-1953), Alicia Bradford Maddox (1875-1920) and Phoebe George Bradford (1794-1840).

Margaretta “Meta” du Pont Coleman (1862-1938) was 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 Margaretta E. "Meta" du Pont Coleman Papers primarily consist of family correspondence collected by Meta Coleman.

Mary Belin (1839-1913) married Lammot du Pont (1831-1884) and had eleven children, many who were prominent in the building up of the E.I. du Pont de Nemours & Company. The volume consists of a typed transcript of letters originally sent to Mary Belin du Pont (1839-1913) by her daughters Louisa ("La") (1868-1926), Sophie M. ("Tabby") (1871-1894), Isabella ("Bella") (1882-1946), and Margaretta ("Peg") (1884-1973) in 1894. The letters center around a single incident wherein Sophie, who was suffering from tuberculosis, was sent to Colorado Springs for a cure.

Sophie Madeleine du Pont (1810-1888) was the youngest daughter of Eleuthère Irénée du Pont (1771-1834), founder of E.I. du Pont de Nemours & Co., and Sophie Madeleine Dalmas du Pont (1775-1828), and the wife of Samuel Francis du Pont (1803-1865). In the letter to Mary Ann (Hogg) Brunot (1822-1899), du Pont thanks her for a sermon Brunot sent and reflects du Pont's concern with religious and domestic matters.

Victor Marie du Pont (1767-1827) was a French diplomat. In 1794, he married Gabrielle Joséphine de La Fite de Pelleport (1770-1837), and a year later they came to the United States, where he was appointed as consul at Charleston, South Carolina. They returned to France in 1798, but came back to the United States in 1800 with their children; his father, Pierre Samuel du Pont de Nemours (1739-1817); and his younger brother, Éleuthère Irénée du Pont (1771-1834), and his family. Victor and Joséphine du Pont had five children, four surviving to adulthood: Amelia Elizabeth (1796-1869), Charles Irénée (1797-1869), Samuel Francis (1803-1865), and Julia Sophie (1806-1882). (The papers of Samuel Francis Du Pont, husband of Sophie Madeleine Du Pont, are held in Group IX of the Winterthur Manuscripts.) The collection is arranged into three series: Amelia du Pont papers, Charles Irénée du Pont and his wives' papers, and Julia (du Pont) Shubrick and her husband, Irvine Shubrick papers. The papers consist primarily of personal correspondence with family and friends.

Wilhelmina du Pont (1906-2000) was the daughter of William K. du Pont (1875-1907) and Ethel Hallock (1876-1951), a fourth generation descendent from E.I. du Pont (1771-1834). The letters are to Wilhelmina du Pont from her cousin Alice (Belin) (Mrs. Pierre S. du Pont) (1872-1944); mother Ethel (Mrs. William Kemble du Pont); cousin Alice (du Pont) (Mrs. T. Coleman du Pont) (1863-1937); and uncle Pierre S. du Pont (1870-1954).