Leo III the Isaurian
As with other Greek territories, Thera then was ruled by the Romans. When the Roman Empire was divided, the island passed to the eastern side of the Empire which today is known as the Byzantine Empire. According to George Cedrenus, the volcano erupted again in the summer of 727, the tenth year of the reign of Leo III the Isaurian. He writes: "In the same year, in the summer, a vapour like an oven's fire boiled up for days out of the middle of the islands of Thera and Therasia from the depths of the sea, and the whole place burned like fire, little by little thickening and turning to stone, and the air seemed to be a fiery torch." This terrifying explosion was interpreted as a divine omen against the worship of religious icons and gave the Emperor Leo III the Isaurian the justification he needed to begin implementing his Iconoclasm policy.