Ninette de Valois was born Edris Stannus to a well-to-do family in County Wicklow, Ireland. When she was seven years old, she moved with her family London, where she took dance lessons and attended the ballet. After studying with the celebrated ballet teacher Enrico Cecchetti and working as a professional dancer in opera, pantomime, and revues, in 1922 she joined the Massine-Lopokova season of Russian ballet in London, taking the elegant stage name Ninette de Valois. The next year, she was invited to join the Ballets Russes of Sergei Diaghilev in Monte Carlo. A few years later, at age 26, she quit performing after learning she was suffering the effects of an undiagnosed case of childhood polio. She founded her own school, the Academy of Choreographic Art, in west London and became the dance director at the avant-garde festival theatre in Cambridge. In 1928, she choreographed four "plays for dancers" at the Abbey Theatre in Dublin. The success of her ballet Job for the Camargo Society in 1931, and her association with Lilian Baylis, director of the Old Vic Theatre, led to the founding of the Vic-Wells Ballet Company and the Sadler’s Wells School in 1931. Besides directing the company and school, she choreographed more than 50 productions, and inspired several generations of British dancers and choreographers. Through them her influence spread to Canada, Australia, Germany, and the USA. Among those whose careers she encouraged were Kenneth Macmillan, John Cranko, Margot Fonteyn, and Rudolf Nureyev. She traced the history of the company, which became the Royal Ballet in 1956, in her books Invitation to the Ballet (1937) and Come Dance with Me (1957). In 1963, she retired as director of the Royal Ballet, although she remained head of the school until 1972. She was created a Dame of the British Empire in 1951, among other honors.