Margaret Osborne was born on a farm in Joseph , Oregon , in 1918 . At the age of nine, her family moved to Spokane , Washington state , where Margaret first came into contact with the game of tennis. Two years later the family moved to San Francisco . There Margaret played on the tennis facility in Golden Gate Park and wrote articles for American Lawn Tennis Magazine . In 1936 she graduated from high school . Since her parents could not finance her college education, she decided to pursue a career as a tennis player. In the same year she won the American youth championships in singles and doubles.
From 1938 Osborne was one of the ten best American tennis players. During the Second World War she worked in a naval shipyard. After the war, she won several singles at the French and US championships and the Wimbledon Championships . She won the US championships in doubles as early as 1941. Between 1946 and 1957 she was one of the ten best tennis players in the world, from 1947 to 1950 she was listed as the world's best tennis player. She won her last mixed title at Wimbledon in 1962 at the age of 44.
From 1938 to 1958 Osborne took part in the Wightman Cup ten times and was able to win all games. The American team won the cup eight times.
In 1947 Osborne married the wealthy businessman William duPont , offspring of the founding family of the chemical company DuPont . The couple settled at the Bellevue Hall family home in Wilmington , Delaware , where Margaret could train on a total of nine tennis courts and all surfaces (hard court, sand, grass). She never took part in the Australian championships because her husband feared that the Australian weather could not be tolerated. The marriage ended in divorce in 1964. After William died a year later, Margaret Osborne moved with her only son William to El Paso , Texas , in a house with her twin partner Margaret Varner Bloss, and devoted herself to horse breeding.