Tiberios was a Germanic army officer originally named Apsimaros (Αψίμαρος). After the admiral John the Patrician retreated from Carthage to Crete in 697, the fleet rebelled, deposed their commander, and chose Apsimaros as his replacement. Apsimaros sailed on Constantinople and besieged it. His revolution attracted detachments from the field army and the imperial guard, and officers loyal to him opened the gates of the city and proclaimed him emperor. The deposed Emperor Leontios had his nose cut off, the same punishment as the one that had been inflicted on his predecessor Justinian II.
As emperor, Tiberios III ignored Africa, where Carthage was now definitively lost, but attacked the Umayyad Caliphate under Abd al-Malik in the east, winning minor victories while raiding into Syria in 701. Arab reprisals in 703 and 704 were repelled from Cilicia. Meanwhile, in 704, Justinian II escaped from exile and made his way back to Constantinople with the help of Tervel of Bulgaria in 705. Managing to enter Constantinople with some of his supporters, Justinian easily regained control, and had Tiberios arrested and executed. A little later the same punishment was inflicted upon Tiberios' brother Herakleios, whom he had appointed strategos of the Anatolic theme.
- The Oxford Dictionary of Byzantium, Oxford University Press, 1991.