Source: TW
The Mongols left behind a laconic account of the end of Ilqa Senggün, the son of Toghrul Wang Khan of the Kereit:
Ilqa [Senggün] fled to the Tangut Kingdom, passing by Isina city and arriving at the [land of the] ‘‘Wolf Tibetans.’’ Having plundered them, he still wished to live there. The ‘‘Wolf Tibetans’’ gathered their peoples and drove him out. [With his forces] scattering, he fled to the land of the Cherkesmen of Küsen (Kucha) city in the west. He was killed by one Qïlïnch-Qara.
This Black Qïlïnch then captured the wife and kid of Senggün & handed them over to Chingiz Khan. Then the Black Qïlïnch submitted voluntarily to Chingiz Khan and joined his ranks. Rashid ad-din clarifies that the Qïlïnch tribe of this ‘‘Black’’ Turk was none other than the Qalaji-s, the same tribe that produced some of the most monstrous tyrants who operated in India. This indicates that some heathen remnants of theirs remained as likely feudatories of the Qara Khitai kingdom and joined the Mongol Khan during the disintegration of the former. Their relationship to the Cherkesmen tribe and the ancient city of Kucha remains mysterious.
Interestingly, ethnographers have noted that a tribe of these Qïlïnch/Qalaji-s have landed up near modern Tehran and still speak an archaic Turkic dialect. This might suggest that they descend from the branch of the tribe that joined the Mongols rather than their counterparts who rampaged in India.
While the Kereit prince met his end in the course of plundering the Tibetans, it is notable that one of the earliest mentions of a Mongolic tribe by the Tibetans is the Kereit. In the Dunhuang manuscript PT 1283, which is a Tibetan record of the Turkic and (Para)Mongolic kingdoms/tribes to their north, we find the mention of the Khereghit (>Kereit in Middle Mongolic) tribe on the steppe. They are said to be to the Northeast, apparently cover their gers with birch bark, and barter pelts of ‘‘blue rodents’’ (=Marmots?) with the Uighurs.
This might mean that Ilqa’s choice of direction might have been informed by an older knowledge of contact with the Tibetans. Moreover, given that PT1283 was composed at the time of the Uighur Khaghanate (~740-840 CE), it would mean that the proto-Kereit had emerged as a distinct Mongolic tribe by then.