It is known that the Sakha ethnonym 'yakut' is considered by some scholars to be an Evenk borrowing, namely, it is associated with the Evenk ethnonym yako 'yakut' [Barashkov, 1985, p. 6; Janhunen, 1982, p. 73-77]. E. I. Ubryatova and a number of other Turkologists point to the process of transition of the Proto-Turkic *y - to Yakut s- through the steps * y - > d- > h - > s -, which occurred, in their opinion, before mass borrowing from the Mongolian and Evenk languages [Ubryatova, 1960, p. 68]. This assumption gives rise to the hypothesis of early medieval contacts between the ancestors of the Yakuts and Evenks, which leads to the hypothesis of the formation of the Yakut language as a result of a language shift among the Evenks, who, due to Turkic influence, switched to a new language and adopted the culture of newcomers. E. I. Ubryatova speaks about the language shift among the Evenks. From her point of view, in the early Middle Ages, at the first stage of the formation of the Yakut language, there was "a joint life of some ancient people, a native speaker of the Turkic language, close to the Orkhon Turkic languages, with some group of Mongols and Evenks" (Ubryatova, 1960, p.12). At the second stage, after the migration of the Yakut Turkic ancestors to the Lena-Aldan interfluve, the Evenks who inhabited this territory switched to the Yakut language. At the last stage, the Yakut language spread among the Evenks outside the Lena-Aldan interfluve, in the Vilyuya, Olekma, Kolyma and in the north [Ubryatova, 1960, p. 12]. Continuing to develop the position of E. I. Ubryatova, N. N. Shirobokova provides evidence for the existence of *y - in the early Yakut language, as well as contacts between the ancestors of the Yakuts and Evenks in the early Middle Ages. In her opinion, this is indicated by the presence of the Evenk word Yakol, meaning Yakuts, and the Russian word yakut, which, according to D. Banzarov, is the Mongolian plural form of the ancient form of self ... Read more