622: A great counterattack is launched against Persia, in which the Persians are successfully driven out of occupied territories in Asia Minor, Egypt, Palestine and Syria.
622-624: Great campaigns on the eastern front, first taking Armenia, then invading Persia.
625: Returns to Anatolia.
626: Persians send troops to aid the Avars who besieged Constantinople. The Byzantines manage to sink the vessels transporting the troops across the Bosporus.
627 December: Byzantine invasion into Persia, leading to an important battle at Nineveh and a devastating defeat of the Persian army.
628 January: Heraclius conquers Dastagird, the royal residence 70 km north of Ctesiphon, with its rich treasure. According to the stories told, Heraclius only demanded that Christ's Cross was returned, together with Byzantine prisoners of war and that Byzantine territory would be given back to him.
629: Heraclius takes the Greek title "basileus", practically abandoning the Latin "augustus". Basileus would remain the title of the emperors of throughout the history of the empire.