Theodosios III

Theodosius III (Greek: Θεοδόσιος, romanized: Theodósios) was the Byzantine emperor from c. May 715 to 25 March 717. Before rising to power and seizing the throne of the Byzantine Empire, he was a tax collector in Adramyttium. In 715, the Byzantine navy and the troops of the Opsician Theme, one of the Byzantine provinces, revolted against Emperor Anastasius II (r. 713–715), acclaiming the reluctant Theodosius as emperor. Theodosius led his troops to Chrysopolis and then Constantinople, the capital, seizing the city in November 715. Anastasius did not surrender until several months later, accepting exile in a monastery in return for safety. Many themes viewed Theodosius to be a puppet of the troops of the Opsician Theme, and his legitimacy was denied by the Anatolics and the Armeniacs under their respective strategoi (generals) Leo the Isaurian and Artabasdos.

Leo declared himself emperor in the summer of 716 and allied himself with the Umayyad Caliphate, the Islamic empire; Theodosius sought aid from the Bulgarians under Khan Tervel (r. 700–721), setting a firm border at Thrace and ceding the Zagoria region to the Bulgarians, as well as stipulating the payment of tribute to them. Leo then marched his troops to Constantinople, seizing the city of Nicomedia, and capturing many officials, including Theodosius's son, also named Theodosius. With his son in captivity, Theodosius took the advice of Patriarch Germanus and the Byzantine Senate, and negotiated with Leo, agreeing to abdicate and recognize Leo as emperor. Leo entered Constantinople and definitively seized power on 25 March 717, allowing Theodosius and his son to retire to a monastery. Exactly when Theodosius died is uncertain, but it may have been on 24 July 754.