This is a collection of the five primary and canonical councils that were held by the Church of the East in Sassanian Mesopotamia in an effort to establish the Christology of the church, as well as its relationship to the Church of the Roman Empire. There are five councils in total, all presides over by the reigning patriarch at the time. These doctrines include the consolidation of power at the capital at Seleucia-Ctesiphon, creating uniformity of the bishops of the church, and establishing the episcopal autonomy of the church from its western counterpart.