The History of the Decline and Fall of the Roman Empire, by Edward Gibbon

Chapter XLVI: Troubles In Persia

Revolutions On Persia After The Death Of Chosroes On Nushirvan.—His Son Hormouz, A Tyrant, Is Deposed.— Usurpation Of Baharam.—Flight And Restoration Of Chosroes II.—His Gratitude To The Romans.—The Chagan Of The Avars.— Revolt Of The Army Against Maurice.—His Death.—Tyranny Of Phocas.—Elevation Of Heraclius.—The Persian War.—Chosroes Subdues Syria, Egypt, And Asia Minor.—Siege Of Constantinople By The Persians And Avars.—Persian Expeditions.—Victories And Triumph Of Heraclius.