First, Sennacherib, in an inscription set up in or about his tenth year (which was B.C.

694), states that he recovered from Babylon certain images of gods, which had been carried thither by Meroclach-idbin-akhi, king of Babylon, who had obtained them in his war with Tiglath-Pileser, king of Assyria, 418 years previously.

This gives for the date of the war with Tiglath-Pileser the year B.C.1112.

As that monarch does not mention the Babylonian war in the annals which relate the events of his early years, we must suppose his defeat to have taken place towards the close of his reign, and assign him the space from B.C.1130 to B.C.1110, as, approximately, that during which he is likely to have held the throne.
Allowing then to the six monumental kings who preceded Tiglath-Pileser average reigns of twenty years each, which is the actual average furnished by the lines of direct descent in Assyria, where the length of each reign is known, and allowing fifty years for the break between Tiglathi-Nin and Bel-kudur-uzur, we are brought to (1130 + 120 + 50) B.C.1300 for the accession of the first Tiglathi-Nin, who took Babylon, and is the first king of whom extensive conquests are recorded.
Secondly.

Sennacherib in another inscription reckons 600 years from his first conquest of Babylon (B.C.