After repulsing the Syrian allies at Qarqar on the Orontes in 854 B.C., Shalmaneser III of Assyria found it necessary to invade Babylonia. Soon after he came to the throne he had formed an alliance with Nabu-aplu-iddin of that kingdom, and was thus able to operate in the north-west without fear of complications with the rival claimant of Mesopotamia. When Nabu-aplu-iddin died, his two sons Marduk-zakir-shum and Marduk-bel-usate were rivals for the throne. The former, the rightful heir, appealed for help to Shalmaneser, and that monarch at once hastened to assert his authority in the southern kingdom. In 851 B.C. Marduk-bel-usate, who was supported by an Aramæan army, was defeated and put to death. Marduk-zakir-shum afterwards reigned over Babylonia as the vassal of Assyria, and Shalmaneser, his overlord, made offerings to the gods at Babylon, Borsippa, and Cuthah. The Chaldæans were afterwards subdued, and compelled to pay annual tribute. In the following year Shalmaneser had to lead an expedition into northern Mesopotamia and suppress a fresh revolt in that troubled region. But the western allies soon gathered strength again, and in 846 B.C. he found it necessary to return with a great army, but was not successful in achieving any permanent success, although he put his enemies to flight. The various western kingdoms, including Damascus, Israel, and Tyre and Sidon, remained unconquered, and continued to conspire against him. The resisting power of the Syrian allies, however, was being greatly weakened by internal revolts, which may have been stirred up by Assyrian emissaries. Edom threw off the yoke of Judah and became independent. Jehoram, who had married Athaliah, a royal princess of Israel, was dead. His son Ahaziah, who succeeded him, joined forces with his cousin and overlord, King Joram of Israel, to assist him in capturing Ramoth-gilead from the king of Damascus. Joram took possession of the city, but was wounded, and returned to Jezreel to be healed.[454] He was the last king of the Omri Dynasty of Israel. The prophet Elisha sent a messenger to Jehu, a military leader, who was at Ramoth-gilead, with a box of oil and the ominous message, "Thus saith the Lord, I have anointed thee king over Israel. And thou shalt smite the house of Ahab thy master, that I may avenge the blood of my servants the prophets, and the blood of all the servants of the Lord, at the hand of Jezebel.... And the dogs shall eat Jezebel in the portion of Jezreel, and there shall be none to bury her." Jehu "conspired against Joram", and then, accompanied by an escort, "rode in a chariot and went to Jezreel", so that he might be the first to announce the revolt to the king whom he was to depose.