Arsenius of Constantinople (Latinised asArsenius Autoreianus;Greek:Ἀρσένιος Αὐτωρειανός;c. 1200 – 30 September 1273),Ecumenical Patriarch of Constantinople, lived about the middle of the 13th century.^[1]

Born inConstantinoplec. 1200 and related to previous PatriarchMichael IV of Constantinople, Arsenius received his education inNicaea at a monastery of which he later became theabbot, though not in orders. Subsequently, he gave himself up to a life of solitary asceticism in aBithynian monastery and is said to have remained some time in a monastery onMount Athos.^[2]

From this seclusion, he was called by theByzantine EmperorTheodore II Laskaris to the position ofpatriarch at Nicaea in 1255.^[2] Upon the emperor's death Arsenius may have shared guardianship of his sonJohn IV Laskaris withGeorge Mouzalon - while the later historiansNicephorus Gregoras andMakarios Melissenos say the Patriarch was so named, the contemporary historiansPachymeres andAcropolites name only Mouzalon.^[3] Nevertheless, a few days after Theodore's death George Mouzalon was murdered byMichael VIII Palaiologos, and who, at an assembly of the aristocracy presided over by Patriarch Arsenius, was appointed regent for the boy. Arsenius also performed the double coronation of Michael VIII Palaiologos and John IV Laskaris in August 1258.^[4]

Through the time between the death of Mouzalon and the double coronation, Arsenius had worked to protect the rights of the young emperor John IV Lascaris, at one point insisting that John IV and Michael VIII exchange mutual oaths of loyalty. He also insisted that at the double coronation John IV Lascaris should be crowned first, which Michael VIII Palaiologos saw as a serious barrier to his final usurpation. Pressure was put upon the patriarch to allow Palaiologos to be crowned alone, and even the young emperor was threatened. The patriarch found no support from the bishops assembled: except for two prelates, all believed that Palaiologos had the right to be crowned first. Arsenius at last conceded the point and crowned Michael VIII and his wife first, while John IV Lascaris received only a special head-dress.^[5]

The ceremony completed, Arsenius took refuge in the monastery of Paschasius, retaining his office of patriarch but refusing to discharge its duties.Nicephorus II of Constantinople was appointed in his stead.Michael VIII Palaiologos, having recoveredConstantinople from theLatin Empire, induced Arsenius to undertake the office of patriarch, but soon incurred Arsenius' severe censure by ordering the young prince John IV to be blinded. Arsenios went so far as toexcommunicate Emperor Michael VIII Palaiologos; after attempting to frighten the patriarch into rescinding the excommunication by threatening to appeal to the Pope, Michael VIII at last convened a synod, had Arsenius deposed, and towards the end of May 1265 sent him into exile.^[6] There he died some years afterwards (according toJohann Albert Fabricius in 1264; others say in 1273).^[2]

Throughout these years Arsenius declined to lift the sentence of excommunication from Michael VIII and after his death, when the new patriarchJoseph I of Constantinople gave absolution to the emperor, the dispute was carried on between the "Arsenites" and the "Josephists". The "Arsenian schism" lasted till 1315, when a reconciliation was pronounced by the patriarchNephon I of Constantinople. Arsenius is said to have prepared the decisions of the councils and the works of theFathers a summary of divine laws under the titleSynopsis Canonum.^{[citation needed]} Some hold thatSynopsis was the work of another Arsenios, a monk of Athos; the ascription depends on whether the patriarch Arsenius did or did not reside at Mount Athos.^[2]

• Nicolas Oikonomidès,"Cinq actes inédits du patriarche Michel Autoreianos",Revue des études byzantines,25 (1967), pp. 113–145

• 1200s births
• 1273 deaths
• 13th-century patriarchs of Constantinople
• People from Constantinople
• People from the Empire of Nicaea
• Byzantine abbots
• 13th-century Christian abbots
• People associated with Mount Athos

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