Eastern Roman Empire (Byzantine Empire) / Emperors Constantine III and Heraklonas

Emperor Heraclius was sole ruler until 22 January 613, when he crowned his son Constantine III as co-emperor.

Towards the end of his reign, Heraclius also named his young son Constantine Heraclius (commonly known by the diminutive Heraklonas) as Augustus on 4 July 638.

On Heraclius's death on 11 February 641, Constantine III and Constantine Heraclius were proclaimed joint emperors. Constantine III died shortly after, leaving Constantine Heraclius as sole ruler.