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.

On his death the crown was seized by Ululâ, who took the name of Shalmaneser IV. His reign lasted only five years, and when he died (December, b.c. 722) he was pressing the siege of Samaria. The capture of the city and its annexation to Assyria were the work of Sargon. The upper and military classes, amounting in all to 27,280 persons, were carried into captivity; but only fifty chariots were found in the city.

Sargon was a usurper like his two predecessors, but, more fortunate than they, he succeeded in founding a dynasty. He was one of the best generals that Assyria ever produced, and under him the extension and organization of the empire went on apace. The death of Shalmaneser, however, had been the signal for revolt in Babylonia as well as in the west. Merodach-baladan, a Chaldaean from the sea-marshes, had seized Babylon in conjunction with the Elamites, and there reigned as legitimate monarch for twelve years. One of the first tasks of Sargon was to drive the Elamite forces from the Assyrian frontier. Hamath moreover rose in insurrection; but this too was speedily crushed. So also was a league between the Philistines and the Egyptians; the battle of Raphia decided, once for all, the question of Assyrian supremacy in Palestine.

Sargon now had to face a more formidable coalition, that of the northern nations under Ursa of Ararat. The struggle lasted for six years and ended with the complete victory of the Assyrians. Carchemish, the Hittite stronghold on the Euphrates, fell in b.c. 717, leaving the road clear to the west and thus uniting Assyria with its rising empire on the shores of the Mediterranean. In the following year the Minni (to the east of Ararat) were overthrown, and two years later Ursa and his allies were utterly defeated. The fortress of Muzazir near Lake Urumiyeh was captured, thus extending the Assyrian frontier far to the east, and Ursa, in despair, committed suicide. Media was completely subdued in b.c. 713, and Ellip, where Ekbatana afterwards stood, became the vassal of Nineveh. In b.c. 711 a league was formed between Merodach-baladan and the nations of southern Syria to resist the common foe, and to this league Egypt promised assistance. But before the confederates were ready to act, Sargon had fallen upon them separately. Ashdod, the centre of the Palestinian confederacy, was besieged and taken (Isaiah xxi), and its ruler, a certain 'Greek,' who had been raised to power by the anti-Assyrian party, fled in vain for refuge to the Arabian desert, while Judah, Edom, and Moab were compelled to pay tribute. In b.c. 709 Merodach-baladan was driven out of Babylonia into his ancestral kingdom of Bit-Yagna. Sargon entered Babylon and there 'took the hands of Bel.' Henceforward he ruled by divine right as well as by the right of the sword.

It was by the sword, however, that he perished, being murdered by a soldier in b.c. 705. His son Sennacherib succeeded to the crown on the 12th of Ab (July). Sennacherib was a different man from his father; boastfulness and vanity took the place of military skill, perhaps also of courage. There seems to have been some resemblance between his character and that of Xerxes.

Babylonia was the new king's first object of attack. Merodach-baladan, who had re-entered Babylon on the news of Sargon's death, was driven back to the marshes, and Bel-ibni, an Assyrian vassal, appointed king in his place. The next campaign was against the Kassi or Kossaeans, some of whom were forced to descend from their mountain fastnesses and placed under an Assyrian governor. From the Kossaean mountains the Assyrian army marched into Ellip which was wasted with fire and sword. Then, in b.c. 701, came the campaign against Palestine where Hezekiah of Judah, in reliance upon Egypt, had revolted from his Assyrian lord. Elulaeus of Sidon fled to Cyprus, and Phoenicia, Ammon, Moab, and Edom submitted to the Assyrians. Sennacherib thereupon proceeded against the Philistines. A new king was set over Ashkelon, and Hezekiah was compelled to restore to Ekron its former prince whom he had imprisoned in Jerusalem on account of his faithfulness to Assyria. The priests and nobles of Ekron who had abetted Hezekiah were impaled on stakes.

Capture of Lachish by Sennacherib.

Tirhakah, the Ethiopian king of Egypt, and the king of Melukh (the Arabian desert), who had come to the assistance of the Jewish prince, were defeated at Eltekeh, and Hezekiah vainly endeavoured to buy off the vengeance of his offended suzerain by rich and numerous presents, including 30 talents of gold and 800 talents of silver. The surrender of Jerusalem alone would content Sennacherib, who accordingly devastated Judah, destroying its cities and carrying into captivity 200,150 of its inhabitants. Jerusalem itself was blockaded, Hezekiah being shut up in it 'like a bird in a cage.' Then, however, came the catastrophe which obliged Sennacherib to retire without punishing his rebellious vassal, and of which, of course, nothing is said in the inscriptions. But there is no further record of a campaign in the West. In the following year Sennacherib was in Babylonia, where he drove Merodach-baladan out of the marshes and obliged the Chaldaean prince and his subjects to fly in ships across the Persian Gulf to the opposite coast of Elam. Assur-nadin-suma, the son of Sennacherib, was now made king of Babylon. Six years later he was carried off to Elam and a new king, Nergal-yusezib, appointed in his place by the Elamite monarch. This was in return for an unprovoked assault made by Sennacherib on the Chaldaean colony in Elam, to which he had crossed in boats made by Tyrian workmen, and whose inhabitants he sent captive to Assyria.