Siege of Constantinople (626)
The siege of Constantinople in 626 by the Sassanid Persians and Avars, aided by large numbers of allied Slavs and Bulgars ended in a strategic victory for the Byzantines. The failure of the siege saved the empire from collapse, and, combined with other victories achieved by Emperor Heraclius (r. 610–641) the previous year and in 627, enabled Byzantium to regain its territories and end the destructive Roman–Persian Wars by enforcing a treaty with borders status quo c. 590. Background In 602, Phocas overthrew Emperor Maurice (r. 582–602). According to the later sources, his reign was marked by atrocities and administrative incompetence. The new emperor's mismanagement left the Byzantine Empire vulnerable and unstable when the Sassanid king Khosrau II (r. 590–628) invaded, using the coup as a pretext for war as Khosrau II was personally close to Maurice, who helped him return his throne after Bahram Chobin's revolt. Initially, the Sassanid invasion was successful, with the Byzantines being driven into the Anatolian heartland. Later, Phocas was overthrown by the son of the then Exarch of Carthage, Heraclius. Heraclius started active warfare and personally led his army into the battle, but the situation deteriorated and the Byzantine empire lost all its Near