In 1207 a new and victorious campaign was begun against Tangut which had failed to pay tribute, but was brought down now, thoroughly, at least, for a season. The subjection of the Kirghis and this new victory over Tangut secured the position of Jinghis in Northeastern Asia. There was not one man now to challenge his dominion. Groups of people, or tribes, might rebel, but there was no power to stop him or modify his policy. He was preparing to meet foreign nations. The first turn was for China. Kara Kitai (Black Cathay) was at that time a very large Empire composed of many nations. The ruler of each of these nations acknowledged the overlordship of the Gurkhan or sovereign. In length Kara Kitai extended westward from Tangut to the Kwaresmian Empire, and in width from the Upper Irtish to the Pamir highlands. Within its borders were the lakes now known as Balkash, Issikkul and Lob Nor. Of cities now existing, Kuldja would be close to the center, Kashgar and Yarkend a good distance from its western border, while Khotan would be well removed from its southernmost limit. Nearly all Central Asia was included in this Empire, while vassal states extended far beyond its western and southwestern borders. The Uigurs, whose chief city was Bish Calik, lived in the northeast corner of the Empire and touched on the Naimans. These Uigurs are famous, at least among scholars, as having been the most devoted to learning of all Turkish nations; from them it was that the Mongols received an alphabet and their earliest instruction. The Idikut, or ruler, of the Uigurs acknowledged the Gurkhan as overlord, but the yearly tribute which he paid, and the daily tyranny of the agent near his court, so annoyed him that he took this official’s life at a place known as Kara Kodja. He resolved thereupon to seek the protection of Jinghis, whose triumphs and whose power were threatening even China, and filling all Asia with amazement and terror. Bardjuk, the watchful Idikut, had appointed an embassy to the conqueror, but events had delayed its departure. When the three sons of Tukta Bijhi and their uncle fled taking their father’s head, which they had cut with all haste from his body on the battlefield, they despatched an envoy in advance to the Idikut to beg a refuge for themselves, and protection. The Idikut, seeing danger in their visit, slew the envoy, took the field against the brothers, and scattered all their forces. But later on he was troubled greatly by this act; for these new opponents might side with the Mongols, or they might join the Gurkhan; they might rouse either party to move against him. The Idikut’s delight was great, therefore, and genuine when Mongol envoys appeared before him. Jinghis had heard of the Idikut’s resolve, and, knowing well what good might rise from it, had taken action very promptly, and despatched as envoys Alp Utug and Durbai to the ruler of the Uigurs.