sentences:  These events also led to the Patriarch of Constantinople centralizing more power in his office, acting alone as the sole Patriarch remaining in the East until the fall of the Byzantine Empire in 1453.Two basic problems—the primacy of the bishop of Rome and the procession of the Holy Spirit—were involved.These doctrinal differences were first openly discussed during the patriarchate of Photius I.
  
  Rome began to interpret her primacy among the Pentarchy of five sees in terms of sovereignty, as a God-given right involving universal jurisdiction in the Church.