Battle of Nineveh (627)

When Emperor Maurice was murdered by the usurper Phocas, Khosrow II declared war under the pretext of avenging his benefactor's death. While the Persians were successful over the course of earlier stages in the war, conquering much of the Levant, Egypt, and even some of Anatolia, the resurgence of Heraclius eventually led to the Persians' downfall. Heraclius' campaigns tilted the balance towards the Romans, forcing the Persians on the defensive. Allied with the Avars, the Persians attempted to take Constantinople, but were defeated. While the Siege of Constantinople was taking place, Heraclius allied with what Byzantine sources called the Khazars under Ziebel, who are identified with the Western Turkic Khaganate of the Göktürks led by Tong Yabghu, plying him with wondrous gifts and a promise of the reward of the porphyrogenita Eudoxia Epiphania. The Caucasus-based Turks responded by sending 40,000 of their men to invade the Caucasus in 626, inciting the Perso-Turkic war of 627–629. Joint Byzantine and Göktürk operations were focused on besieging Tiflis. ==Invasion of Mesopotamia==

In mid-September 627, leaving Ziebel to continue the Siege of Tbilisi, Heraclius invaded the Persian Empire, this time with between 25,000 and 50,000 troops and 40,000 Göktürks. The Göktürks, however, quickly deserted him because of the strange winter conditions. capital of Nineveh in Assuristan (Assyria) province. Persian reinforcements were near Mosul. After the battle, Heraclius went back east while the Persians looped back to Nineveh itself before following Heraclius again.|thumb|left|Maneuvers before and after the Battle of Nineveh On 1 December, Heraclius crossed the Great Zab River and camped near the ruins of the capital of the former Assyrian Empire of Nineveh in Persian ruled Assyria/Assuristan. This was a movement from south to north, contrary to the expectation of a southward advance. However, this can be seen as a way to avoid being trapped by the Persian army in case of a defeat. Rhahzadh approached Nineveh from a different position. News that 3,000 Persian reinforcements were approaching reached Heraclius, forcing him to counteract. ==Field of battle==

Heraclius had found a plain west of the Great Zab some distance from the ruins of Nineveh. This allowed the Byzantines to take advantage of their strengths in lances and hand-to-hand combat. Furthermore, fog reduced the Persian advantage in missile-shooting soldiers and allowed the Byzantines to charge without great losses from missile barrages. ==Battle==

On 12 December, Rhahzadh deployed his forces into three masses and attacked. Heraclius feigned retreat to lead the Persians to the plains before reversing his troops to the surprise of the Persians. 6,000 Persians fell. Nikephoros' Brief History tells that Rhahzadh challenged Heraclius to single combat. Heraclius accepted and killed Rhahzadh in a single thrust; two other challengers fought and also lost. ==Aftermath==

and Heraclius receiving the submission of Khosrow II; plaque from a cross (Champlevé enamel over gilt copper, 1160–1170, Paris, Louvre) The victory at Nineveh was not total as the Byzantines were unable to capture the Persian camp. However, the victory was effective in preventing further Persian resistance. Khosrow had already fled to the mountains of Susiana to try to rally support for the defense of Ctesiphon. Heraclius could not attack Ctesiphon itself because the Nahrawan Canal was blocked by the collapse of a bridge. Kavad immediately sent peace offers to Heraclius. Heraclius did not impose harsh terms, knowing that his own empire was also near exhaustion. Under the peace treaty, the Byzantines regained all their lost territories, their captured soldiers, a war indemnity, and of great spiritual significance, the True Cross and other relics that were lost in Jerusalem in 614. The battle was the last conflict of the Roman–Persian Wars. ==References==