John A. Costello
3rd Taoiseach from 1948 to 1951, and 1954 to 1957
John Aloysius Costello (20 June 1891 – 5 January 1976) was an Irish Fine Gael politician who served as Taoiseach from 1948 to 1951 and from 1954 to 1957. He was leader of the opposition from 1951 to 1954 and from 1957 to 1959 and attorney general from 1926 to 1932. He served as a Teachta Dála (TD) from 1933 to 1943 and from 1944 to 1969.
Early life
Costello was born on 20 June 1891, in Fairview, Dublin. He was the younger son of John Costello senior, a civil servant, and Rose Callaghan. He was educated at St Joseph's, Fairview and then moved to O'Connell School for senior classes. He later attended University College Dublin, where he graduated with a degree in modern languages and law. He studied at King's Inns to become a barrister, winning the Victoria Prize there in 1913 and 1914.
Costello was called to the Irish Bar in 1914 and practised as a barrister until 1922.
Irish Free State
In 1922, Costello joined the staff at the office of the attorney general in the newly established Irish Free State.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 19, 2026. The linked authority identifier is Q381690. VIAF identifies the subject as 111105669. The Library of Congress control number is no96053876. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1891, 1976, 1948 and 1951.
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This entry incorporates text from “John A. Costello” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.