After the
Council of Chalcedon, Peter Mongus was an ardent adherent of
Miaphysitism and deacon of
Timothy Aelurus. After Timothy expelled the Chalcedonian
Patriarch Proterius in 457, Mongus took part in the persecution of the Chalcedonians. When Timothy Aelurus, who had been expelled in 460 and returned in 475, died in 477, his followers elected Mongus to succeed him. However, the
Byzantine Emperor Zeno brought
Timothy Salophakiolos, a Chalcedonian who had supplanted Aelurus before in 460, back to Alexandria and sentenced Mongus to death. Mongus escaped by flight and remained in hiding until 482. In the previous year,
John Talaia had succeeded Timothy Salophakiolos as patriarch. However, as Talaia refused to sign Emperor Zeno's
Henoticon (which glossed over the Council of Chalcedon), the emperor expelled him and recognized Mongus as the legitimate patriarch on the condition that he would sign the Henoticon. Mongus complied and after taking possession of the see, he signed the controversial document and sent notice of his succession to his fellow patriarchs.
Patriarch Acacius of Constantinople entered him into his diptychs as
patriarch of Alexandria. Talaia had meanwhile fled to Rome, where he was welcomed by
Pope Felix III, who refused to recognize Mongus and defended Talaia's rights in two letters to Acacius. As Acacius maintained the Henoticon and communion with Mongus, the pope excommunicated the patriarchs in 484. This
Acacian schism lasted until 519. Mongus became the chief champion of all Miaphysites. He held a synod to condemn Chalcedon, and desecrated the tombs of his two Chalcedonian predecessors Proterios and Timothy Salophakiolos. When Acacius died in 489, Mongus encouraged his successor
Fravitta to maintain the schism with Rome. Fravitta's successor
Euphemius sought to heal the schism by
excommunicating Mongus, who however died soon afterwards in 490. ==Works==