His son Esar-haddon, who succeeded him (681-669 BC) after his murder by two other sons on the 20th Tebet (compare 2Ki 19:37), was as distinguished a general and administrator as his father had been the reverse. For his history see ESARHADDON .
Under him the Second Empire reached the acme of its power and prosperity. Babylon was rebuilt and made the second capital of the empire, Palestine became an obedient province, and Egypt was conquered (674 and 671 BC), while an invasion of the Cimmerians (Gomer) was repelled, and campaigns were made into the heart of both Media and Arabia. Esar-haddon died while on his way to repress a revolt in Egypt, and his son Assur-bani-pal succeeded him in the empire (669-626 BC), while another son Samas-sum-ukin was appointed viceroy of Babylonia.
Assur-bani-pal was a munificent patron of learning, and the library of Nineveh owed most of its treasures to him, but extravagant luxury had now invaded the court, and the king conducted his wars through his' generals, while he himself remained at home. The great palace at Kouyunjik (Nineveh) was built by him. Egypt demanded his first attention.
Tirhakah the Ethiopian who had headed its revolt was driven back to his own country, and for a time there was peace. Then under Tandamane, Tirhakah's successor, Egypt revolted again. This time the Assyrian punishment was merciless. Thebes--"No-amon" (Na 3:8)--was destroyed, its booty carried away and two obelisks transported to Nineveh as trophies of victory. Meanwhile Tyre, which had rebelled, was forced to sue for peace, and ambassadors arrived from Gyges of Lydia asking for help against the Cimmerians. Elam still remained independent and endeavored to stir up disaffection in Babylonia.
Against his will, therefore, Assur-bani-pal was obliged to interfere in the internal affairs of that country, with the result that the Elamites were finally overthrown in a battle on the Eulaeus beneath the walls of Susa, and the conquered land divided between two vassal kings.
Then suddenly a revolt broke out throughout the greater part of the Assyrian empire, headed by Assur-bani-pal's brother, the viceroy of Babylonia. For a time the issue was doubtful. Egypt recovered its independence under Psammetichus, the founder of the XXVIth Dynasty (660 BC) who had received help from Lydia, but Babylonia was reconquered and Babylon after a long siege was starved out, Samas-sum-ukin burning himself in the ruins of his palace. Elam remained to be dealt with, and an Assyrian army made its way to Susa, which was leveled to the ground, the shrines of its gods profaned and the bones of its ancient kings torn from their graves.
Then came the turn of northern Arabia, where the rebel sheikhs were compelled to submit. But the struggle had exhausted Assyria; its exchequer was empty, and its fighting population killed. When the Cimmerians descended upon the empire shortly afterward, it was no longer in a condition to resist them. Under Assur-etil-ilani, the son and successor of Assur-bani-pal, Calah was taken and sacked, and two reigns later, Sin-sar-iskun, the last king of Assyria, fell fighting against the Scythians (606 BC). Nineveh was utterly destroyed, never again to be inhabited, and northern Babylonia passed into the hands of Nabopolassar, the viceroy of Babylon, who had joined the northern invaders.(emphasis added) Assur, the old capital of the country, was still standing in the age of Cyrus, but it had become a small provincial town; as for Nineveh and Calah, their very sites were forgotten.
No wonder you are so confused!
You don't even know basic history!