Description: A central figure in the division of the Church and a major influence in both the domestic and foreign politics of the Eastern Empire, Nicholas I was one of the most prominent patriarchs of Constantinople. His correspondence collected in Nicholas I, Patriarch of Constantinople: Letters is a historical source of the first importance.
Brief description: R. J. H. Jenkins (1907-1969) was Professor of Byzantine History and Literature at Harvard University and Director of Byzantine Studies Emeritus at the Dumbarton Oaks Research Library and Collection.