The article examines the demographic and national structure of Belarus in light of the national census which took place in early 1999. That census demonstrated how the political, social, and economic transformation of the last decade influenced demography and ethnic composition in Belarus, as well as the national identity of its citizens. One such example is the Chernobyl catastrophe, which spurred migration within the Republic and also awakened the Belarusians' consciousness of national distinctness. In the period between the census of 1959 and the recent one, a permanent and significant increase in the Russian population and a limited growth of the Belorussian population were observed; simultaneously, the Polish and Jewish populations declined. The 1999 census demonstrated that this tendency was halted: the number of Russians declined (they left Belarus), while the Belarusian population increased (they keep returning home from other republics of the former Soviet empire). The article also considers the status of the Belarusian language, which is the first language of 73.7 % of citizens of Belarus, although only 36.7 % of Belarusians use it in everyday communication. Thus, the dominant position is occupied by the Russian language, which is used in everyday communication by 63 % of people of Belarus. The favored position of Russian is fostered by the policies of Alexander Lukashenko, the President of the Republic.