Waldorf Astor was born on May 19, 1879, in New York City, New York, the eldest son of William Waldorf Astor, 1st Viscount Astor (1848-1919).

He was an American-born English politician and newspaper proprietor, a member of the legendary Astor family. He spent much of his life travelling and living in Europe before his family settled in England in 1889. Waldorf attended Eton College and New College, Oxford, where he excelled as a sportsman, earning accolades for both fencing and polo. In 1905, while a passenger on an Atlantic voyage returning to Britain, Astor met Nancy Langhorne Shaw (1879-1964), a divorced woman with a young son (Robert Gould Shaw III). Coincidentally, both he and Mrs. Shaw shared the same birthdate, May 19, 1879, and both were American. After a rapid courtship, the two married in May 1906 and settled at the Astor family estate in Cliveden. Nancy encouraged her husband to launch a career in politics. He entered Parliament in 1910, acting as secretary to Prime Minister David Lloyd George in 1917. He retired from public office in 1919, his seat being taken by his wife, Nancy Witcher, Viscountess Astor, the first woman to sit in the British House of Commons. Astor was proprietor of The Observer, a London Sunday newspaper formerly owned by his father (to whose title he succeeded in 1919), from 1919 to 1945, when he turned it over to a trust. Astor became governor of the Peabody Trust and Guy's Hospital. His interest in international relations fuelled his involvement with the Royal Institute of International Affairs, and he served as its chairman from 1935 to 1949. He was also a considerable benefactor to the city of Plymouth and served as its Lord Mayor from 1939 to 1944. Astor was appointed Honorary Colonel of the Devonport, Plymouth-based Devonshire Heavy Brigade, Royal Artillery of the Territorial Army in 1929. An authority on agricultural problems, Astor became chairman in 1936 of a committee that was the progenitor of the Food and Agriculture Organization (FAO) of the United Nations.

He died on September 30, 1952, in Cliveden, Buckinghamshire, England.