Theodosius III resigns the throne to the Byzantine Empire to enter a monastery, allowing Leo III to take the throne and begin the Isaurian dynasty.

Theodosius III 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…