Alfred Irénée duPont (1864-1935) was born on May 12, 1864, in a stone house near the banks of the Brandywine River in Delaware. He was a descendent of the duPont family of French nobility who emigrated to America during the French Revolution and established the powder manufacturing dynasty of Eleutherian Mills. Alfred was the third child and first son of Eleuthère Irénée duPont (1829-1877) and Charlotte S. Henderson (1835-1877). He had four siblings: Anne Cazenove duPont Walker (1860-1899); Marguerite duPont Lee (1862-1936); Maurice (1866-1941); and Louis Cazenove (1868-1892). The five children were orphaned at an early age when both parents died, within weeks of each other, in 1877.

Although Alfred inherited a considerable amount of property, he grew up in the powder mill working and fighting on equal terms with the sons of Irish and Italian laborers. He possessed a keen intellect and a powerful physique, as well as musical and mechanical aptitudes, but had limited interest in formal education. Throughout his life he prided himself on being a self-made man. In his youth he gained the reputation of being "the best black powder man in the nation" and the mechanical genius of the duPont family.

In 1902, Alfred was bold enough to claim the company his elders wanted to sell to their major competitor, Laflin and Rand. With two cousins, Thomas Coleman duPont and Pierre Samuel duPont, he formed a triumvirate which converted the old gunpowder company into the E. I. duPont de Nemours Powder Company in 1903. The great duPont chemical empire of today eventually evolved from this enterprise. The reorganization also precipitated an unbreechable division of the duPont family as the cousins vied for control of the company through stock manipulation and lawsuits. Alfred was shut out of the company in 1915 and bitterly turned to other business and political pursuits. At one time he owned several Delaware newspapers and used them to oppose the election of Thomas Coleman duPont and Henry A. duPont to state offices and to the United States Senate.

Concurrent with the family business war was Alfred's unhappy marriage to his first wife, Bessie Gardner (1864-1949). Married in 1887, the couple had four children: Madeleine duPont (Bancroft) (Hiebler) Ruoff (1887-1965); Bessie duPont Huidekoper (1889-1973); Alfred Victor (1900-1970); and Victorine duPont Dent (1903-1965). In 1904 Alfred lost an eye in a hunting accident and shortly afterwards his marriage ended in a scandalous divorce resulting in alienation of his children and intensified animosity within the extended family.

Alfred's second marriage in 1907 was to his beautiful but melancholy cousin, Alicia Bradford Maddox (1875-1920) who never overcame the deaths of her two infant children. In an effort to please his new wife, Alfred began a lifelong project: the design and development of his Nemours estate in Wilmington, Delaware. It consisted of a seventy-seven room house, forest, gardens, and working farm. Alicia, however, preferred to spend much of her time in Paris while Alfred pursued his endless construction and engineering projects, yachting, sports, politics, and far-flung business dealings. Alicia died in 1920, leaving him with the care of their five-year-old French-born foster daughter, Adelaide Camille Denise (Denise duPont Zapffe after her marriage to Carl A. Zapffe). He was also responsible for the guardianship of her daughter, Alicia Amory Maddox (Glendening) (Llewllyn) (Kent) (Fraser) MacGregor.

In 1898 while hunting in Virginia, Alfred became acquainted with the Balls, a distinguished southern family which had been impoverished by the Civil War. He developed a lasting friendship with their fourteen-year-old daughter Jessie, twenty years Alfred's junior, which eventually led to their marriage after Alicia's death in 1920. Jessie was a peacemaker and reconciled Alfred with his children from his first marriage and other family members. Consequently, Alfred found the happiness with Jessie which had eluded him in earlier years.

In 1926 Alfred and Jessie decided to move their principal residence from Nemours to Epping Forest in Jacksonville, Florida. He opened offices in Jacksonville and founded Almours Securities, Inc. At this point his assets were reported to total over $34,000,000 and his business enterprises virtually dominated the economy of Florida. Until his death in 1935, Alfred devoted himself to Jessie, yachting, travel, his beloved dogs, real estate, and the support of numerous charities during the era of the Great Depression. These charitable enterprises were continued and vastly expanded by Jessie Ball duPont in the years following Alfred's death.