Heraclius is the brother of the Byzantine emperor Tiberius III (r. 698–705) and the Byzantine Empire's leading general during his reign.

He scores a number of victories against the Umayyads, but is unable to halt the Arab conquest of Armenia, nor able to prevent the deposition of his brother by Justinian II (r. 685–695 and 705–711), who later captures and executes them both.