This article suggests that the Trans-Baikal region until the middle of the 17th century was a part of the area inhabited by the medieval Dahurs (Daurs). The thesis that the “Old Barguts” had their homeland in the Baikal region is defended; the reasons for their leaving the original territory and the time of departure are identifi ed. The article poses the question about the role of the Daurs and the Barguts in shaping the indigenous population of the Baikal region, and identifi es the traces of these peoples in local toponymy.
