Pope Marinus I
Pope Marinus I was the bishop of Rome and ruler of the Papal States from 882 until his death on 15 May 884. Controversially at the time, he was already a bishop when he became pope, and had served as papal legate to Constantinople. He was also erroneously called Pope Martin II leading to the second pope named Martin to take the name Martin IV.
Ecclesiastical career
Diplomat to the East
Born at Gallese, Marinus was the son of a priest. He would become an expert on relations with the Eastern church, starting this path when he assisted as subdeacon the welcome of ambassadors of emperor Michael III in 860. He was ordained as a deacon by Pope Nicholas I and then sent in 866 to Constantinople to discuss the religious leadership over the newly converted Bulgarians though the embassy was turned back at the Byzantine border. Marinus was sent again in 869 as one of pope Adrian II's legates who presided over the eighth ecumenical council in Constantinople which deposed the Patriarch Photios I of Constantinople. His profile became popular after and some time afterwards he became bishop of Caere, possibly to prevent that he could become archbishop of Bulgaria as one of king Boris' favourite candidates.On three separate occasions, he had been employed by the three popes who preceded him as legate to Constantinople, his mission in each case having reference to the controversy started by Patriarch Photios I of Constantinople. In 882, he was sent on behalf of Pope John VIII to Duke Athanasius of Naples to warn him not to trade with the Muslims of southern Italy. During that time, he also served as treasurer to the Holy See.