High Quality Content by WIKIPEDIA articles! In the history of Christianity, the first seven ecumenical councils, from the First Council of Nicaea (325) to the Second Council of Nicaea (787), represented an attempt to reach an orthodox consensus and to establish a unified Christendom as the state church of the Roman Empire. The East-West Schism, formally dated to 1054, was still almost three centuries off from the last of these councils, but already by 787 the major western sees, although still in communion with the state church of the Byzantine Empire, were all outside the empire, and the Pope was to crown Charlemagne as emperor 13 years later.