Constantine III

Constantine III was a Byzantine emperor who briefly reigned from January to April or May 641. He had been co-emperor with his father, Heraclius, since 613 and later shared power with his brother, Heraclonas, starting in 638.

Constantine's rise to power is intertwined with the tumultuous events of Roman Britain. In early 407, he was acclaimed emperor by the field army in Britain. Quickly seizing the opportunity, he moved his forces, led by his commander Gerontius, to Gaul (modern France), taking all mobile troops from Britain. Facing Germanic invaders who had crossed the Rhine during the previous winter, Constantine employed both military strength and diplomacy to stabilize the region, eventually extending his authority over Gaul and Hispania (modern Spain and Portugal). He established his capital at Arles, solidifying his control.