Tiglath-pileser reigned eighteen years (B.C. 745-727), and his organizing abilities proved to be as great as his military skill. An invasion of Babylonia first tested the strength of his army, and resulted in the subjection of the Aramaean tribes in that country to Assyrian rule. Then followed an expedition into Kurdistan. The Medes were massacred, and the Assyrian army pushed its way far eastward to Bikni, 'the mountain of the rising sun.' Next Tiglath-pileser turned to the north-west. Here he was met by a powerful confederacy, at the head of which was the king of Ararat. But the forces of the northern nations were cut to pieces in Komagene, and Arpad, which had become the centre of a hostile Syrian league, was captured after a siege of three years. The league had included Hamath and Azariah of Judah, and Hamath was consequently annexed to the Assyrian empire. The princes of the West hastened to offer homage to the conqueror, among them being Rezon of Damascus and Menahem of Samaria (B.C. 738). Tiglath-pileser was now free to march against Ararat, which had extended its power at the expense of Assyria in the later days of the old dynasty. The country was ravaged up to the gates of its capital, and the Vannic kingdom received a blow from which it never recovered. The Assyrian army next turned eastward to the southern shores of the Caspian, and made its way through Medic and other districts which neither before nor since were trodden by Assyrian feet. The exploit struck terror into the Kurdish tribes, and secured the Assyrian lowlands from their attack. Meanwhile Ahaz of Judah had been threatened by Rezon of Damascus and Pekah of Israel, and he now appealed to the Assyrian king for help. Tiglath-pileser, nothing loth, marched against the assailants. Rezon was blockaded in his capital, while Samaria, Ammon, Moab, and Philistia were overrun (B.C. 734). Two years later (B.C. 732), Damascus was taken and sacked, Rezon put to death and his kingdom placed under an Assyrian prefect. Pekah, too, had been murdered, and Tiglath-pileser had appointed Hosea king in his place. About the same time Tyre was compelled to purchase peace by the payment of 150 talents. With his empire consolidated in the west, and the road to the Mediterranean open to Assyrian trade, Tiglath-pileser was now free to legitimize his right to the throne by occupying Babylon and there becoming the adopted son of Bel. It was in B.C. 731 that the Babylonian campaign began; in B.C. 729 Tiglath-pileser, under his original name of Pul, 'took the hands of Bel,' and two years later, in the month of December, he died. He had introduced into history the idea of imperial centralization.