THE BISHOP OF ROME AND THE ECUMENICAL COUNCIL OF CHALCEDON, AD 451: WHY POPE LEO I’S DOCTRINAL AND DISCIPLINARY DEMANDS WERE MET By Shaun Retallick A Thesis submitted to the Faculty of the University of St. Michael’s College and the Historical Department of the Toronto School of Theology in partial fulfilment of the requirements for the degree of Master of Arts in Theology Awarded by the University of St. Michael’s College. Toronto 2011 © Shaun D. W. Retallick