Dynamics of the Mordovians number in the union republics of the USSR

The external parameters of the ecumene include the ethnos number and its dynamics. In the course of the historical process, the Mordovian population on the territory of the near abroad republics (in the Union Republics of the USSR) varied according to natural and climatic, social and economic factors. The history of population migration and the Mordovian population formation in the CIS countries is recorded by the results of the censuses of the Russian Empire and the USSR. The dynamics of the Union republics Mordovians can be traced by censuses of Byelorussia, Kazakhstan, Uzbekistan, Ukraine, etc. Statistical data are confirmed by documents extracted from fund 473 of the Mordovian SSR State Committee on labor and social issues of the Republic of Mordovia Central State Archives. There are folders with various decrees, edicts, plans for interregional migration in the Mordovian ASSR; lists and questionnaires of settlers, acts-lists on workers transferred to enterprises, application forms compiled for resettlers, etc. The purpose of the study is to analyze the types of documentary sources and create a picture of the Mordovian population dynamics on the territory of the near abroad countries (the former Soviet Union Republics). A wide range of documentary sources made it possible to create the picture of the Mordovians migration in Belarus, Kazakhstan, Uzbekistan, Ukraine, and others.