Tiberios III (-706), originally named Apsimaros, was a Germanic naval officer in the Byzantine fleet. He participated in the failed campaign to regain Carthage from the Umayyad Caliphate, and joined the fleet in rebellion against Emperor Leontios rather than admitting defeat. Apsimaros changed his name to Tiberios, and sailed to Constantinople to besiege it. Constantinople soon fell to Tiberios' forces, and he claimed the throne for himself in 698, cutting off Leontios' nose and exiling him to a monastery. As emperor, he made the tactical decision to ignore Africa, ensuring Carthage was definitively lost to the Byzantine Empire. He appointed his brother Herakleios with the task of fighting the Caliphate in the East, winning many victories against the Arabs. In 705, former emperor Justinian II escaped from exile and led an army of Khazars to attack Constantinople, entering the city through abandoned water conduits beneath the city to take it from within. Tiberios had fled to Bithynia by then, evading capture for several months before he was finally brought back to the capital. Tiberios and former emperor Leontios was paraded in chains through the city before being mutilated and executed at Justinian's orders in 706.