Arsenius Autorianus

Arsenius Autorianus (c. 1204-c. 1273), patriarch of Constantinople (present day İstanbul). His deposition caused a serious schism in the Byzantine Church. He was born in Constantinople and educated at a monastery in Nicaea (now İznik, Turkey). He later retired to a monastery near Lake Apollonias in the ancient country of Bithynia.

In 1254 Arsenius was appointed patriarch by the Byzantine emperor Theodore II Lascaris. When the emperor died four years later, Arsenius became a guardian to his son John IV Lascaris. Another guardian, Michael VIII Palaeologus, seized power by violent means and assumed regency in John’s stead. Arsenius escaped but was induced to return and resume his duties as patriarch. When Michael banished and blinded John, the rightful heir to the throne, Arsenius excommunicated the emperor. Michael, after vainly attempting to obtain the patriarch's pardon, had Arsenius deposed and exiled to the island of Proconnesus. The deposition caused the Byzantine Church to divide into two opposing groups. The first group was known as the Arsenites, or followers of Arsenius, while the second, known as the Josephites, were the followers of Joseph, Arsenius’s second successor. The schism continued officially until 1310, when Arsenius’s body was laid to rest in the Hagia Sophia, a church in Constantinople.