Lady Nancy Witcher Langhorne Astor, known as Viscountess Astor, was born on May 19, 1879, in Danville, Virginia.

She was an American-born British politician who was the first woman seated as a Member of Parliament (MP), serving from 1919 to 1945. Raised in Albemarle County, Virginia, by a Confederate veteran father who made his fortune in the railroad boom, she was a noted beauty in her time. She and her four sisters were collectively called the "Gibson Girls" from images created by her older sister Irene's husband, painter Charles Dana Gibson. She attended a finishing school in New York City, where she met her first husband, the socialite Robert Gould Shaw II (1872-1930). Moving to England in the early 1900s following a broken marriage, she quickly became a much-desired member of high society. After meeting Waldorf Astor (1879-1952), a child of the legendary Astor family, she married him in 1906 and established herself as mistress of Cliveden, the couple's Buckinghamshire estate. Playing hostess to a wide circle of upper-crust friends, she was also liked by the general populace because of her charitable activities which included setting up a World War I hospital for Canadian soldiers on her property, where she personally helped care for the wounded troops. When her husband succeeded to his father's title and seat in the House of Lords in 1919, Lady Astor stood as the Conservative candidate for Plymouth. Her effort was handicapped by her prohibitionism, lack of political experience, and knack for saying outrageous things, but was helped by her good looks and nature, willingness to moderate her views, and genuine devotion to her constituents. During most of her 25 years in Parliament, she proved popular and energetic, though with time her anti-Catholic and anti-Semitic views caused comment and the term "Cliveden Set" became, probably unjustly, a synonym for "Nazi." During World War II, she again established a hospital on her estate, but she was showing early signs of mental decline and reluctantly retired from Parliament in 1945. Thoroughly established in her adopted land, Nancy never lost her identity as an American and more especially as a Virginian, visiting frequently over the years, donating both money and artifact collections to the University of Virginia during the 1930s, and contributing materially to the 1929 restoration of Stratford Hall, Robert E. Lee's Westmoreland County birthplace and ancestral home.

Gradually isolated as her health deteriorated, she became a virtual recluse prior to her death on May 2, 1964, at her daughter's home in Grimsthorpe, England.