What the Babylonian chronologists called 'the First Dynasty of Babylon' fell in its turn, and it is claimed that a Sumerian line of eleven kings took its place. Their sway lasted for 368 years--a statement which is obviously open to question. These were themselves overthrown and a Kassite dynasty from the mountains of Elam was founded by Kandis (_c_. 1780 B.C.) which lasted for nearly six centuries. These alien monarchs failed to retain their hold on much of the Asiatic and Syrian territory which had paid tribute to Babylon and the suzerainty of Palestine was likewise lost to them. It was at this epoch, too, that the high-priests of Asshur in the north took the title of king, but they appear to have been subservient to Babylon in some degree. Assyria grew gradually in power. Its people were hardier and more warlike than the art-loving and religious folk of Babylon, and little by little they encroached upon the weakness of the southern kingdom until at length an affair of tragic proportions entitled them to direct interference in Babylonian politics. A Court Murder The circumstances which necessitated this intervention are not unlike those of the assassination of King Alexander of Serbia and Draga, his Queen, that happened 3000 years later. The Kassite king of Babylonia had married the daughter of Assur-yuballidh of Assyria. But the match did not meet with the approval of the Kassite faction at court, which murdered the bridegroom-king. This atrocious act met with swift vengeance at the hands of Assur-yuballidh of Assyria, the bride's father, a monarch of active and statesmanlike qualities, the author of the celebrated series of letters to Amen-hetep IV of Egypt, unearthed at Tel-el-Amarna. He led a punitive army into Babylonia, hurled from the throne the pretender placed there by the Kassite faction, and replaced him with a scion of the legitimate royal stock. This king, Burna-buryas, reigned for over twenty years, and upon his decease the Assyrians, still nominally the vassals of the Babylonian Crown, declared themselves independent of it. Not content with such a revolutionary measure, under Shalmaneser I (1300 B.C.) they laid claim to the suzerainty of the Tigris-Euphrates region, and extended their conquests even to the boundaries of far Cappadocia, the Hittites and numerous other confederacies submitting to their yoke. Shalmaneser's son, Tukulti-in-Aristi, took the city of Babylon, slew its king, Bitilyasu, and thus completely shattered the claim of the older state to supremacy. He had reigned in Babylon for some seven years when he was faced by a popular revolt, which seems to have been headed by his own son, Assur-nazir-pal, who slew him and placed Hadad-nadin-akhi on the throne. This king conquered and killed the Assyrian monarch of his time, Bel-kudur-uzur, the last of the old Assyrian royal line, whose death necessitated the institution of a new dynasty, the fifth monarch of which was the famous Tiglath-pileser I.