1. Of Constantinople, surnamed Autorianus, lived about the middle of the thirteenth century.
He was educated in some monastery in Nicaea, of which he afterwards became the head. After he had held this office for some time, he led a private and ascetic life; and he appears to have passed some time also in one of the monasteries on mount Athos. At length, about A. D. 1255, the emperor Theodorus Lascaris the Younger raised him to the dignity of patriarch. In A. D. 1259, when the emperor died, he appointed Arsenius and Georgius Muzalo guardians to his son Joannes; but when Muzalo began to harbour treacherous designs against the young prince, Arsenius, indignant at such faithless intrigues, resigned the office of patriarch, and withdrew to a monastery. In A. D. 1260, when the Greeks had recovered possession of Constantinople under Michael Palaeologus, Arsenius was invited to the imperial city, and requested to resume the dignity of patriarch. In the year following, the emperor Michael Palaeologus ordered prince Joannes, the son of Theodorus Lascaris, to be blinded; and Arsenius not only censured this act of the emperor publicly, but punished him for it with excommunication. Michael in vain implored forgiveness, till at length, enraged at such presumption, he assembled a council of bishops, brought several fictitious accusations against his patriarch, and caused him to be deposed and exiled to Proconnesus. Here Arsenius survived his honourable disgrace for several years; but the time of his death is unknown. Fabricius places it in A. D. 1264. He was a man of great virtue and piety, but totally unfit for practical life.