John of Cappadocia was an Eastern Orthodox priest who served as the Ecumenical Patriarch of Constantinople between 518 and 520. Appointed by his predecessor, Timothy I, he held this high office during the transition from the reign of Anastasius I to Emperor Justin I. His brief tenure is most notable for managing the intense religious fervor of the Constantinopolitan populace, which led to the restoration of the Council of Chalcedon's decrees and the eventual reconciliation between the Eastern and Western churches after a long schism.