Greek Orthodox patriarch of Antioch (1089-1118).
John was a monk in the monastery of Oxeia on the Sea of Marmara when he was appointed patriarch of Antioch (mod. Antakya, Turkey) by Alexios I Komnenos, the Byzantine emperor, perhaps at the instigation of the influential empress-mother Anne Dalassena. In September 1089 he participated as newly ordained patriarch in a synod convoked by Patriarch Nicholas III Grammatikos of Constantinople to discuss a letter of Pope Urban II, in which the Pope requested the introduction of his name in the diptychs of the Greek Orthodox church. At this synod John criticized frankly many abuses in church, state, and society.
Diplomatic contacts between Emperor Alexios and the Saljûq sultan Malik Shāh I enabled John to travel via Cyprus to Antioch in autumn 1091 to take up his appointment as patriarch under Turkish rule. After the conquest of the city (4 June 1098) by the armies of the First Crusade, the crusaders recognized John as the legal patriarch, but during the next two years his relationship with the Latins deteriorated. After the capture of Prince Bohemund I of Antioch by the Turks in August 1100, the Latins suspected that John was planning to hand over the city to Alexios Komnenos. They forced him to withdraw to Constantinople, where he abdicated from the patriarchate in October 1100. Around 1112 he wrote a treatise against the use of unleavened bread (azymes) in the Eucharist by the Latins.