HERACLEONAS, East Roman emperor (Feb.–Sept. 641), was the son of Heraclius (q.v.) and Martina. At the end of Heraclius' reign he obtained through his mother's influence the title of Augustus (638), and after his father's death was pro claimed joint emperor with his half-brother Constantine III. The premature death of Constantine, in May 641, left Heracleonas sole ruler. But a suspicion that he and Martina had murdered Constantine led soon after to a revolt, and to the mutilation and banishment of the supposed offenders. Nothing is known about Heracleonas after 641.