John Vernou "Black Jack" Bouvier III (May 19, 1891 – August 3, 1957) was an American socialite and Wall Street stockbroker. He was the father of former First Lady Jacqueline Kennedy Onassis and Lee Radziwill. His nickname was "Black Jack", referring to his omnipresent dark tan and his flamboyant lifestyle.

Bouvier was born in East Hampton, New York. He was the eldest of five children born to Major John Vernou Bouvier, Jr. (1865—1948) and Maude Frances Sergeant (1870—1940). Black Jack's great-grandfather, Michel Bouvier (1792–1874), was a French cabinetmaker who left France in 1815 after the defeat of Napoleon; he settled in Philadelphia, where he opened a cabinet making or furniture shop, making fine furniture for customers including Stephen Girard and Joseph Bonaparte, Napoleon's brother who lived for a time on his estate, Point Breeze in Bordentown, New Jersey.

Michel gained his fortune later in real estate speculation. His son, Michel Charles (M.C.) Bouvier, further distinguished himself in the world offinance on Wall Street. M.C. left his fortune to his nephew, Major John Vernou Bouvier, Jr., who used it to buy an estate in East Hampton, Long Island, known as Lasata.

Black Jack had a younger brother, William Sergeant "Bud" Bouvier (1893–1929), who died prematurely from alcoholism, and three younger sisters, Maude R. Bouvier Davis, Michelle C. Bouvier Scott Putnam, and Edith Ewing Bouvier (wife of Phelan Beale, Sr., mother of Edith Bouvier Beale,Phelan Beale, Jr., and Bouvier Beale).[1][2][3]

Bouvier served in World War I and attended Sheffield Scientific School of Yale University, graduating in 1914. He then became a stockbroker.[4] He married Janet Norton Lee on July 7, 1928, with whom he had two daughters, Jacqueline Lee "Jackie" Bouvier and Caroline Lee Bouvier.

Black Jack's drinking, gambling, and philandering led to his divorce from his wife in 1940. He did not remarry. In 1942, Janet married Hugh Dudley Auchincloss, Jr. Janet reportedly did not want Black Jack to escort Jacqueline down the aisle for her wedding to John F. Kennedy, so Jacqueline was instead escorted by her stepfather Auchincloss. Some reports indicate Bouvier was too intoxicated to escort his daughter, leading Auchincloss to step in to give the bride away.

He lived at 125 East 74th Street.[5] Bouvier died at 66 in New York City, New York, and is buried in the Bouvier family plot at Most Holy Trinity Catholic Cemetery in East Hampton, New York

John Bouvier