Costello, John Aloysius, << kah STEHL oh or KAHS tuh `loh, john al oh IHSH uhs` >> (1891-1976), served as prime minister of Ireland from 1948 to 1951 and from 1954 to 1957. In 1948, Costello, then head of the Fine Gael party, took control of the Irish Free State from Eamon de Valera, who had led the state for 16 years. Costello declared the state an independent republic in 1949. De Valera was prime minister between Costello’s terms, and, in 1957, his victory ended Costello’s second term.
Costello was born on June 20, 1891, in Dublin and received a law degree. He served as attorney general of the Irish Free State from 1926 to 1932. Costello died on Jan. 5, 1976. See also De Valera, Eamon; Ireland, History of (The Republic of Ireland).