The monograph, based on archaeological, linguistic and written data, examines the ethnogenetic problems of Eastern Zakamye from the Iron Age to the late Middle Ages. In the culture of the ancient population of the region, the authors identify the Finnish, Ugric and Samoyed strata. The history of the study of "Great Hungary" - a vast Ugric country, which in the Middle Ages included the eastern regions of Tatarstan, is widely covered.