The Council of Chalcedon in 451 was a defining moment in the Christological controversies that tore apart the churches of the Eastern Roman Empire in the fifth and sixth centuries, as theological division, political rivalry, and sectarian violence produced a schism that persists to this day between Chalcedonian and non-Chalcedonian churches. The Acts of the Councils are one of the largest collections of source materials relating to the Church of Late Antiquity and its state relations, and this volume places the acclaimed translation in context with the Council of Chalcedon of 451, ultimately informing historians on how to approach manifold aspects of these documents.