Cearbhall Ó Dálaigh
Ó Dálaigh trained as a lawyer.  He became Ireland's youngest Attorney-General in 1946 under Taoiseach Éamon de Valera. He was re-appointed as Attorney-General in 1951 and in 1953 he became the youngest member of the Supreme Court. Less than a decade later, he became the youngest Chief Justice of Ireland.