John Aidan Costello (Gaelic: Eoin Aodhan MacCostello) (September 10, 1901 - May 9, 1994) was an Irish politician and soldier best known for serving as the commander of the Irish forces in England during the Irish intervention in the English Anarchy, a military campaign he later became a fierce critic of. Costello became a moderate, secular Conservative politician in the Dail Eireann after retiring from the army in 1964 and was a two-time Presidential candidate, running in 1967 and 1971. Costello is credited for helping repair the Irish right and install a new intellectual renaissance for the Conservative Party, which came to represent the Irish center-right as the opposition party after the decline of the Christian Democrats. He declined to run in the 1976 general election to contest the P