The northern and eastern boundaries of the empire were at length secured. It was now necessary to punish the Arab tribes who had taken advantage of the Kimmerian invasion to harass the empire on the south. Esar-haddon accordingly marched into the very heart of the Arabian desert—a military achievement of the first rank, the memory of which was not forgotten for years. The empire at last was secure.

The Assyrian king was now free to complete the policy of Tiglath-pileser by conquering Egypt. Palestine was no longer a source of trouble. Judah had returned to its vassalage to Assyria, and the abortive attempts of Sidon and Jerusalem to rebel had been easily suppressed. True to his policy of conciliation, Esar-haddon had dealt leniently with Manasseh of Judah. He had been brought in fetters before his lord at Babylon, and there pardoned and restored to his kingdom. It was a lesson which neither he nor his successors forgot, like the similar lesson impressed a few years later upon the Egyptian prince Necho.

The Assyrian conquest of Egypt has been already described. The first campaign of Esar-haddon against it was undertaken in B.C. 674; and it was while on the march to put down a revolt in B.C. 668 that he fell ill and died, on the 10th of Marchesvan, or October. The empire was divided between his two sons. Assur-bani-pal had already been named as his successor, and now took Assyria, while Saul-sum-yukin became king of Babylonia, subject, however, to his brother at Nineveh. It was an attempt to flatter the Babylonians by giving them a king of their own, while at the same time keeping the supreme power in Assyrian hands.

The first few years of Assur-bani-pal's reign were spent in tranquillising Egypt by means of the sword, in suppressing insurrections, and in expelling Ethiopian invaders. After the destruction of Thebes in B.C. 661 the country sullenly submitted to the foreign rule; its strength was exhausted, and its leaders and priesthood were scattered and bankrupt. Elam was now almost the only civilised kingdom of western Asia which remained independent. It was, moreover, a perpetual thorn in the side of the Assyrians. It was always ready to give the same help to the disaffected in Babylonia that Egypt was to the rebels in Palestine, with the difference that whereas the Egyptians were an unwarlike race, the Elamites were a nation of warriors. Assur-bani-pal was not a soldier himself, and he would have preferred remaining at peace with his warlike neighbour. But Elamite raids made this impossible, and the constant civil wars in Elam resulting from disputed successions to the throne afforded pretexts and favourable opportunities for invading it. The Elamites, however, defended themselves bravely, and it was only after a struggle of many years, when their cities had fallen one by one, and Shushan, the capital, was itself destroyed, that Elam became an Assyrian province. The conquerors, however, found it a profitless desert, wasted by fire and sword, and in the struggle to possess it their own resources had been drained and well-nigh exhausted.

The second Assyrian empire was now at the zenith of its power. Ambassadors came from Ararat and from Gyges of Lydia to offer homage, and to ask the help of the great king against the Kimmerian and Scythian hordes. His fame spread to Europe; the whole of the civilised world acknowledged his supremacy.

But the image was one which had feet of clay. The empire had been won by the sword, and the sword alone kept it together. Suddenly a revolt broke out which shook it to its foundations. Babylonia took the lead; the other subject nations followed in its train.

Saul-suma-yukin had become naturalised in Babylonia. The experiment of appointing an Assyrian prince as viceroy had failed; he had identified himself with his subjects, and like them dreamed of independence. He adopted the style and titles of the ancient Babylonian mouarchs; even the Sumerian language was revived in public documents, and the son of Esar-haddon put himself at the head of a national movement. The Assyrian supremacy was rejected, and once more Babylon was free.

The revolt lasted for some years. When it began we do not know; but it was not till B.C. 648 that it was finally suppressed, and Saul-suma-yukin put to death after a reign of twenty years. Babylon had been closely invested, and was at last starved into surrender. But, taught by the experience of the past, Assur-bani-pal did not treat it severely. The leaders of the revolt, it is true, were punished, but the city and people were spared, and its shrines, like those of Kutha and Sippara, were purified, while penitential psalms were sung to appease the angry deities, and the daily sacrifices which had been interrupted were restored. A certain Kandalanu was made viceroy, perhaps with the title of king.

Chastisement was now taken upon the Arabian tribes who had joined in the revolt. But Egypt was lost to the empire for ever. Psammetikhos had seized the opportunity of shaking off the yoke of the foreigner, and with the help of the troops sent by Gyges from Lydia, had driven out the Assyrian garrisons and overcome his brother satraps.

Assur-bani-pal was in no position to punish him. The war with Elam and the revolt of Babylonia had drained the country of its fighting men and the treasury of its resources. And a new and formidable enemy had appeared on the scene. The Scyths had followed closely on the footsteps of the Kimmerians, and were now pouring into Asia like locusts, and ravaging everything in their path. The earlier chapters of Jeremiah are darkened by the horrors of the Scythian invasion of Palestine, and Assur-bani-pal refers with a sigh of relief to the death of that "limb of Satan," the Scythian king Tugdamme or Lygdamis. This seems to have happened in Cilicia, and Assyria was allowed a short interval of rest.