Éamon de Valera (; first registered as George de Valero; changed in 1910 to Edward de Valera; 14 October 1882 – 29 August 1975) was one of the dominant political figures in twentieth-century Ireland. His political career spanned over half a century, from 1917 to 1973; he served several terms as head of government and head of state. He also led the introduction of the Constitution of Ireland.