Nancy Mitford, styled The Hon. Nancy Mitford before her marriage and The Hon. Mrs Peter Rodd thereafter, was an English novelist and biographer, one of the Bright Young People on the London social scene in the inter-war years. She was born at 1 Graham Street (now Graham Place) in Belgravia, London, the eldest daughter of Lord Redesdale, and was brought up at Asthall Manor in Oxfordshire. She was the eldest of the six controversial Mitford sisters.

She is best remembered for her series of novels about upper-class life in England and France, particularly the four published after 1945; but she also wrote four well-received, well-researched popular biographies (of Louis XIV, Madame de Pompadour, Voltaire, and Frederick the Great). She was one of the noted Mitford sisters and the first to publicize the extraordinary family life of her very English and very eccentric family, giving rise to a "Mitford industry," which continues.