Sybil Thorndike was born in Gainsborough in 1882. She trained as a pianist but decided on theatre and in 1904 appeared in The Merry Wives of Windsor.
After spending four years touring the United States with a Shakespearean Repertory Company she returned to England and became a leading figure in Annie Horniman's Repertory Company in Manchester. She also worked at the Old Vic (1914-19). Thorndike established herself as Britain's leading actress in Saint Joan (1924) by George Bernard Shaw.
Thorndike took a keen interest in politics and was a supporter of the Popular Front government in Spain during the Spanish Civil War. She joined with Emma Goldman, Rebecca West, Fenner Brockway and C. E. M. Joad to establish the Committee to Aid Homeless Spanish Women and Children.
During the Second World War Thorndike was a leading figure in the Old Vic Company. Sybil Thorndike died in 1976.