In this Quick Hit I cover the victory of the Byzantine army under Heraclius over Persian Sassanid forces. On a plain not far from the rubble of the ancient Assyrian City of Nineveh, Byzantine cataphracts used superior numbers and generalship to bring an end to a decades long war with their eastern enemy. The end of the centuries long conflict known as the Roman-Persian Wars left a power vacuum in the Middle East and it would not be long before that vacuum was filled. An exhausted Byzantium and a crippled Persia meant there was little to slow the rise of the Arabic armies and the march of Islam.