Rashid ad-Din on the "Kyrgyz Tribe"
According to Rashid ad-Din's information about the "Kyrgyz tribe," it is stated in the "Collection of Chronicles" that "Kyrgyz and Këm-Këmjiut are two adjacent regions; both constitute one dominion (mamlakat). Këm-Këmjiut is a large river, one side of which borders the territory of the Mongols (Moghulistan), and one (its) boundary is with the Selenga River, where the Taichiut tribes reside; one side borders the (basin of the) great river, which is called Ankara-muren, reaching the limits of the Ibir-Siber region. One side of Këm-Këmjiut borders the lands and mountains where the Nayman tribes reside. The tribes of Kori, Bargu, Tumat, and Bayaut, some of whom are Mongols and inhabit the region of Bargudzhin-Tokum, are also close to this area. There are many cities and settlements in these regions, and the nomads are numerous.
The title (of each) of their sovereign, even if he had another name, is inal, and the family name of those from this area who are respected and known is idi. Their sovereign was ... (omission). The name of another region is Yedi-Orun, and the sovereign there was called Uruz-inal."
In Rashid ad-Din's account of the settlement of the Nayman tribes, it is mentioned that they inhabited the area between "Irdysh-muren, which is the Irtysh River," and the mountains lying "between that river and the Kyrgyz region, bordering the limits of that country (i.e., the Kyrgyz - E. u. K.)." Furthermore, the areas of settlement of the Naymans reached "to the lands of Moghulistan" and "to the region where On-khan lived — for this reason, there was constant strife and enmity between the Naymans and On-khan." The boundary of the settlement of the Nayman tribes reached "to the Kyrgyz region and to the borders of the deserts," which bordered the land of the Uyghurs. "These tribes (of Naymans) were nomadic; some lived in very mountainous places, while others lived in the plains."
According to Rashid ad-Din's information, the land of the Kyrgyz could encompass the territories of the Ob-Irtysh interfluve (in the northwest of Altai), Upper (Tuva), and Middle (Minusinsk Basin) Yenisei. It is possible that the area of "Këm-Këmjiut" covered the aforementioned regions of Upper and Middle Yenisei, while the area of "Kyrgyz," respectively, covered the western regions of the Kyrgyz land, up to the Irtysh region. Alternatively, the area of "Kyrgyz" could have included territories from the Ob-Irtysh interfluve and further east, including the regions of Middle Yenisei (Minusinsk Basin), while the area of "Këm-Këmjiut" encompassed the lands of Upper Yenisei (Tuva).
These territories (i.e., the area of "Këm-Këmjiut") could represent regions that were within the sphere of influence of the Kyrgyz or subordinate to them. If Rashid ad-Din's report is accurate that one boundary of "Këm-Këmjiut" reached the Selenga River, "where the Taichiut tribes reside...", then these lands likely also fell within the limits of the area of "Këm-Këmjiut" at that time. Incidentally, I. V. Berezin, referring to Ritter, writes that "the name Këm-Këmjiut comes from the rivers Kema and Kemchik, Little Kema."