The Battle of Niḫriya was the culminating point of the hostilities between the Hittites and the Assyrians for control over the remnants of the former empire of Mitanni in Upper Mesopotamia, in the second half of the 13th Century BC.
When Hittite king Šuppiluliuma I (r. c. 1344–1322 BC) conquered Mitanni, he created two provinces (Aleppo and Carchemish), and distributed the large part of territories of this kingdom among his allies. The rest of what had been the empire of Mitanni retained its independence as a Hittite vassal state called Ḫanigalbat. During the reign of the Hittite king Muršili III (better known as Urḫi-Teššub), Ḫanigalbat was subjugated by the Assyrians, who now advanced to the East bank of the Euphrates. When Ḫattusili III (r. c. 1267–1237 BC) ousted his nephew Muršili III and seized the Hittite throne, he had to be content with the permanent loss of Ḫanigalbat to the Assyrians despite its former status as a Hittite vassal state. Nevertheless, the Assyrians encountered repeated opposition by their new vassals, the kings of Ḫanigalbat, who naturally looked upon the Hittites as their allies.
