 Seventh-day Adventists teach that great apostasy corresponded with the rise of the power of the Roman Bishop which they see as the Little Horn Power of Daniel 7 prophecy, which as predicted rose after the breakup of the Roman Empire.In 533 A.D. Justinian, the emperor of the Eastern Roman Empire, legally recognized the bishop (pope) of Rome as the head of all the Christian churches.Because of the Arian domination of some of the Roman Empire by the barbarian tribes, this authority could not be exercised by the bishop of Rome.