For a time Elam was all-powerful in Babylonia, though Nergal-yusezib had been defeated and captured in battle by the Assyrians. But in b.c. 691 Sennacherib descended with the full might of Assyria upon the country. The Babylonians had sent the treasures of the temple of Bel to the Elamite monarch, begging his help. The Babylonian and Elamite forces met the army of Assyria at Khalule, and a hard-fought battle was the result. The slaughter was great on both sides, and Sennacherib claims a complete victory, though the Babylonian Chronicle—a cuneiform document compiled from a Babylonian point of view—implies that such was not altogether the case. At all events about two years were needed for the subjugation of Babylonia. In b.c. 689 Babylon was taken, its houses and temples destroyed, the images of its gods broken in pieces, and the ruins of the city thrown into the Arakhtu, the canal of Babylon. For some years Babylon lay desolate, and as there was no longer a temple or image of Bel to legitimize the rule of the Assyrian conqueror, Babylonia remained 'without kings.'
On the 20th day of Tebet or December, b.c. 681, Sennacherib was murdered by two of his sons who seem to have been jealous of their brother Esar-haddon. Esar-haddon had been given the new name of Assur-etil-mukin-abla ('Assur the hero is the establisher of my son'), perhaps because he had been destined for the throne, and at the time of his father's murder he was commanding the Assyrian army in a war against Ararat. For forty-two days the conspirators held the capital; then they were compelled to fly to Erimenas of Ararat and seek his help against their brother. The decisive battle was fought on the 12th of Iyyar (April) near Malatiyeh in Kappadokia; the veterans of Assyria won the day, and at the close of it saluted Esar-haddon as king. He returned to Nineveh and on the 8th of Sivan (May) formally ascended the throne.
Esar-haddon was great in counsel as well as in war, and knew how to conciliate as well as how to conquer. At the outset of his reign he restored Babylon, rebuilt its temples, brought back its gods and people, and made it one of his royal residences. For twelve years he was king alike of Babylonia and Assyria.
A revolt of Sidon, which was easily put down, next occupied his attention. Then came a more formidable event. The Gimirrâ, called Gomer in Genesis, Kimmerians by the Greeks, suddenly appeared out of the north and menaced the civilized world. Esar-haddon met them on the frontier of his empire, defeated their chieftain, the 'Manda' or nomad Teuspa, and drove his hordes westward into Asia Minor. It now became necessary to secure the Assyrian frontier on the south. The Assyrian king accordingly marched into the very heart of Arabia, through burning and waterless deserts, and struck terror into the Arabian tribes. The march must have been one of the most remarkable ever made.
Esar-haddon was at last free to complete the policy of Tiglath-pileser III by conquering the ancient kingdom of Egypt. Palestine gave no more trouble; Manasseh of Judah was already an obedient vassal of the Assyrian king. In b.c. 674 'the Assyrians marched into Egypt.' But two more campaigns were needed for its subjection. In b.c. 670 Esar-haddon drove the Egyptian forces before him in fifteen days (from the 3rd to the 18th of Tammuz or June) all the way from the frontier to Memphis, thrice defeating them with heavy loss and wounding Tirhakah their king. Three days later Memphis fell, and Tirhakah fled to Ethiopia, leaving Egypt to the conqueror. Egypt revolted two years afterwards (b.c. 668), and while on the march to reduce it Esar-haddon fell ill, and died on the 10th of Marchesvan or October. Assur-bani-pal, who had already been named as his successor, became king of Assyria, his brother Saul-suma-yukin taking Babylonia as his share. The king of Babylonia, however, was required to admit the supremacy of the Assyrian monarch.
The Egyptian revolt was quickly suppressed and the country was again divided into twenty satrapies, each satrapy being placed under a native prince. But the arrangement answered badly. The satraps quarrelled with one another, intrigued with Tirhakah, and rebelled against Assur-bani-pal. Time after time Assyrian armies had to be sent to reconquer the land. Once Necho, the satrap of Sais, was brought in chains to Nineveh, there, however, to be pardoned and restored to his city. Twice Thebes was captured, once after it had been made for a time the seat of Tirhakah's government, a second time after the defeat of Urdaman (Rud-Amon), the step-son and successor of Tirhakah. On this occasion the city was utterly destroyed. Its temples and palaces were overthrown, its statues mutilated, and an immense spoil carried away to Nineveh. Among the spoil were two obelisks, over seventy tons in weight. The destruction of Thebes is alluded to by the prophet Nahum (iii. 8).
Assur-bani-pal, the Sardanapallos of the Greeks, was the 'Grand Monarque' of Assyria, and a generous patron of literature and learning. But he lacked the warlike instincts of his fathers, and preferred to remain at home while his generals fought in the field. His long wars drained the country of its fighting-men and prepared the way for its downfall. They were waged mainly with Elam, the only civilized country of Western Asia which still preserved its independence, and lasted for several years. At last, however, Elam fell; its capital Shushan was sacked and burned, and a desolated country was added to the Assyrian dominions.
The fame of Assur-bani-pal spread far and wide. Ambassadors came to his court from Ararat, as well as from Gyges of Lydia. At first no interpreter could be found for the latter. Gyges wanted help against the Kimmerians, which, however, 'the great king' does not seem to have afforded. The tribute of Gyges was accordingly withdrawn after a time, and he took part in the great rebellion which now shook the Assyrian empire to its foundations.
Saul-suma-yukin put himself at its head, and proclaimed the independence of Babylonia. Psammetikhos, the son of Necho of Sais, imitated his example in Egypt, and with the assistance of Gyges put down the rival satraps, shook off the Assyrian yoke and founded the Twenty-sixth dynasty. Saul-suma-yukin was less fortunate. After a desperate struggle he was captured and put to death by his brother, and Babylonia was once more reduced to servitude. Punishment was also taken upon the tribes of northern Arabia who had joined the rebels.
But the empire was terribly weakened. Egypt was lost to it for ever, and though Elam was added instead, it proved to be a barren possession. When Tuktamme the 'Manda' appeared upon the scene he was resisted with difficulty. The empire was tottering to its fall.