Athenagoras I (Greek:Αθηναγόρας Αʹ), born Aristocles Matthew Spyrou (Greek:Αριστοκλής Ματθαίος Σπύρου; 6 April [O.S. 25 March] 1886 – July 7, 1972), initially the Greek archbishop in North America, was the 268th Ecumenical Patriarch of Constantinople, from 1948 to 1972.