Though the earliest kings[740] and dynasties of the Hittites remain unknown, the nature of the Hittite organisation in the thirteenth and fourteenth centuries B.C. is now made clear by the archives recently discovered at Boghaz-Keui. These cover the reigns of six generations of the Hatti dynasty of kings, making allusion in all to eight of their sovereigns. They include treaties with internal states in Syria and elsewhere, with Mitanni, with the Amorites, and with Egypt, most of them prefaced by historical notes of events leading up to the conclusion of the treaty in question. There is also correspondence of a diplomatic character with the courts of Thebes, of Babylonia and of Mitanni, and other documents of varied sorts. These are written in cuneiform, and the language employed in foreign affairs is the Assyro-Babylonian: only in some internal matters the Hittite language is used. Though the documents have not yet disclosed the full nature of their contents, the archives as a whole[741] have already thrown as much light upon the history of the Hittites at this period as did the Tell el Amarna tablets, with which they are in part contemporary, on the foreign affairs of Egypt during the eighteenth dynasty. The story opens with a bid for empire under the Hatti leadership in the person of Subbi-luliuma.[742] This ruler (known in Egyptian records as Sapalulu) had inherited only the kingship of his city-state of Kû-sar [or Sû-sar], which was possibly at Boghaz-Keui itself, from his father, Hattusil I.; but so well were his plans laid, and so accomplished his military leadership, that before his death he had won for himself the title of Great King.[743] We cannot follow the story of his doings in Asia Minor, for unfortunately the names of the places mentioned in Hittite in this and the succeeding reign cannot yet be identified; but it will be clear from what follows that his western frontiers, if not already peopled by Hittite tribes and subject to his authority, must have claimed his first attention. In other directions his policy and movements are revealed more clearly. Among his own peoples he seems to have arranged a series of alliances; other lands which he overran he parcelled out among his followers, while to some non-Hittite tribes he granted terms of vassalage.