Joseph Early Widener (August 19, 1871 – October 26, 1943) was a wealthy American art collector who was a founding benefactor of the National Gallery of Art in Washington, D.C. A major figure in thoroughbred horse racing, he was head of New York's Belmont Park and builder of Miami's Hialeah Park racetrack in Florida.

Widener's steeplechase horses won numerous important races including three editions of the American Grand National with Relluf (1914), Arc Light (1929), and Bushranger (1936).

For his Elmendorf Farm breeding operation, Widener acquired Belmont's very important sire Fair Play and the broodmare Mahubah, the parents of Man o' War.

Widener's father had had business interests in France and like other wealthy elite Americans of that era, maintained a place in fashionable Paris.

Designed by Horace Trumbauer and Jacques Greber, the mansion, along with its extensive and important art collection, was part of the huge fortune he inherited.

Hailed as one of the most beautiful Thoroughbred race tracks in the world, in 1979 Hialeah Park was listed on the United States National Register of Historic Places.

Major races here were the Widener Handicap inaugurated in 1936, and the Flamingo Stakes, an important stepping stone to the Kentucky Derby for 3-year-old horses.

In 1939, Widener made a number of donations from his assorted collections including manuscripts of historical and artistic importance given to the Rare Book Department at the Free Library of Philadelphia.