Since the early 4th century AD, Christianity had become the established religion in the Roman Empire, supplanting pagan polytheism and eclipsing for the most part the humanistic world outlook and institutions inherited from the Greek and Roman civilizations. Ecclesiastical records during the Slavic invasions are slim. Though the country was in the fold of Byzantium, Christians in the region remained under the jurisdiction of the Roman pope until 732. In that year the iconoclast Byzantine emperor Leo III, angered by archbishops of the region because they had supported Rome in the Iconoclastic Controversy, detached the church of the province from the Roman pope and placed it under the patriarch of Constantinople. When the Christian church split in 1054 between the East and Rome, southern Albanian regions retained their ties to Constantinople while the northern areas reverted to the jurisdiction of Rome.