MANUEL I COMNENUS, Emperor of Byzantium. — Son of John Comnenus and Pirska (Irene), a Hungarian princess; he ruled the empire from 1143 to 1180. The ideal of a restoration of the Universal Empire, which guided his policy, led him to intervene in Italy against the Normans first (1143-58), then against Barbarossa, in Hungary, in Anatolia against the sultan of Iconium, and in Syria against Nūr al-Dīn to protect the Frankish colonies. This same ideal inspired his repeated attempts at religious union with Rome and with the Churches of Armenia and Syria.
The conflicts that arose between the papacy and Frederick Barbarossa led Manuel to hope that he might replace the German Emperor as protector of the Holy See; he offered his support to Adrian IV, and to his successor Alexander III he proposed in 1166 the union with the Greek Church, provided that he himself be recognized as sole emperor. Although the Pope declared that he could not accept such proposals, his relations with Manuel remained good, and in 1176 at Anagni Manuel appears among the allies of the Holy See.
In the East, the consolidation of Byzantine rule led to negotiations for union with Nerses, catholicos of the Armenians. In May 1170 theological conferences took place in which a delegate of the celebrated patriarch of Antioch, Michael the Syrian, also participated. The declared opposition of the Armenian clergy rendered these negotiations fruitless, as did those undertaken later (1175, 1177, 1179) under catholicos Gregory IV Dgha (1173-93).
Manuel actively intervened in the numerous theological disputes that arose within the Byzantine Church. He promoted the condemnation of the monk Niphon, accused of Bogomilism but protected by Patriarch Cosmas (1146-47). Also condemned was Demetrius of Lampe, who misinterpreted the words of Christ “The Father is greater than I,” Soterichos Panteugenes and others who maintained that the eucharistic sacrifice is offered only to the Father and the Holy Spirit. Finally, Manuel had to face strong opposition from the Byzantine clergy for having wished to suppress an anathema customarily recited by Muslims who converted to Christianity, which might have offended their sensibilities.