In 649, according to the Liber Pontificalis, the Byzantine Emperor Constans II ordered Olympius to arrest Pope Martin I on the grounds that the pope's election had not been submitted to the emperor for approval. Constans was upset with Martin's condemnation of the Monothelite heresy; he feared that it would resurrect the religious conflict that had plagued the empire. Olympius attempted to gain the support of the citizenry of Rome, as well as the bishops; he also allegedly considered ordering the assassination of Martin. None of his actions, however, met with much success.
Eventually Olympius decided to switch his allegiance and sided with the Pope, simultaneously declaring himself emperor. He marched into Sicily in 652, either to fight the Saracens or the local Byzantine forces. His army was stricken by an unknown disease, which killed Olympius that same year.
- Jeffrey Richards, The Popes and the Papacy in the Early Middle Ages (London:Routledge and Kegan Paul, 1979), pp. 187f
- Raymond Davis (translator), The Book of Pontiffs (Liber Pontificalis), first edition (Liverpool: University Press, 1989), pp. 69f
- A. N. Stratos, "The Exarch Olympius and the Supposed Arab Invasion of Sicily in A.D. 652", Jahrbuch der Österreichischen Byzantinistik, 25 (1976), 63-73.
| Exarch of Ravenna
Theodore I Calliopas