Battle of Nineveh
627 CE.
Shown on the map at 36.359°, 43.153°.
The Battle of Nineveh was the climactic battle of the Byzantine–Sasanian War of 602–628. In mid-September 627, Heraclius invaded Sasanian Mesopotamia in a surprising, risky winter campaign. Khosrow II appointed Rhahzadh as the commander of an army to confront him. Heraclius' Göktürk allies quickly deserted, while Rhahzadh's reinforcements did not arrive in time. In the ensuing battle, Rhahzadh was slain and the remaining Sasanian forces retreated. The Byzantine victory later resulted in civil war in Persia, and for a period of time restored the (Eastern) Roman Empire to its ancient boundaries in West Asia. The Sasanian civil war significantly weakened the Sasanian Empire, contributing to the Muslim conquest of Persia.
Text from the Wikipedia article Battle of Nineveh (627), licensed CC BY-SA 4.0.