Nabonassar appears to have lived on friendly terms with Tiglath-Pileser, the contemporary monarch of Assyria, who early in his reign invaded the southern country, reduced several princes of the districts about Babylon to subjection, and forced Merodach-Baladan, who had succeeded his father, Yakin, in the low region, to become his tributary. No war seems to have been waged between Tiglath-Pileser and Nabonassar. The king of Babylon may have seen with satisfaction the humiliation of his immediate neighbors and rivals, and may have felt that their subjugation rather improved than weakened his own position. At any rate it tended to place him before the nation as their only hope and champion—the sole barrier which protected their country from a return of the old servitude.
Nabonassar held the throne of Babylon for fourteen years, from B.C. 747 to B.C. 733. It has generally been supposed that this period is the same with that regarded by Herodotus as constituting the reign of Semiramis. As the wife or as the mother of Nabonassar, that lady (according to many) directed the affairs of the Babylonian state on behalf of her husband or her son. The theory is not devoid of a certain plausibility, and it is no doubt possible that it may be true; but at present it is a mere conjecture, wholly unconfirmed by the native records; and we may question whether on the whole it is not more probable that the Semiramis of Herodotus is misplaced. In a former volume it was shown that a Semiramis flourished in Assyria towards the end of the ninth and the beginning of the eighth centuries B.C.—–during the period, that is, of Babylonian subjection to Assyria. She may have been a Babylonian princess, and have exercised an authority in the southern capital. It would seem therefore to be more probable that she is the individual whom Herodotus intends, though he has placed her about half a century too late, than that there were two persons of the same name within so short a time, both queens, and both ruling in Mesopotamia.
Nabonassar was succeeded in the year B.C. 733 by a certain Nadius, who is suspected to have been among the independent princes reduced to subjection by Tiglath-Pileser in his Babylonian expedition. Nadius reigned only two years—from B.C. 733 to B.C. 731—when he was succeeded by Ghinzinus and Porus, two princes whose joint rule lasted from B.C. 731 to B.C. 726. They were followed by an Elulseus, who has been identified with the king of that name called by Menander king of Tyre—the Luliya of the cuneiform inscriptions; but it is in the highest degree improbable that one and the same monarch should have borne sway both in Phoenicia and Chaldaea at a time when Assyria was paramount over the whole of the intervening country. Elulseus therefore must be assigned to the same class of utterly obscure monarchs with his predecessors, Porus, Chinzinus, and Nadius; and it is only with Merodach-Baladan, his successor, that the darkness becomes a little dispelled, and we once more see the Babylonian throne occupied by a prince of some reputation and indeed celebrity.