The Battle of Kār Ištar was a battle fought between Assyria and the Kassites of Babylon sometime during the reign of Assyrian king Adad-nirari I. Under the reign of Assyrian King Ashur-uballit I, the Assyrians destroyed Mitanni, a kingdom in northern Mesopotamia that had dominated Assyria politically since the 1450's BCE. Ashur-uballit's victory allowed Assyria to become the Middle Assyrian Empire, a major Mespotamian power. This put them on a crash course with the major city of southern Mesopotamia, Babylon, currently ruled by the Kassite Peoples. Ashur-Uballit waged war with the Babylonians, defeating them and taking much territory. However this dominance appears to have been lost as Adad-nirari I recalls how his father (Arik-den-ili) "could not rectify the calamities inflicted by the ki