This article discusses the Belarusian case of post-communist development and the role and status of Belarusian ethnicity in Belarus' nation-formation process. "Nationalizing nationalism" (Brubaker), as realised by the Belarusian state through various social and cultural practices, is aimed at the creation of a Belarusian national entity without reference to the ethnocultural core of Belarusians. As a result of the nationalising practices of the Belarusian state, most Belarusians identify with their nation-state while displaying weak identification with ethnicity. At the same time, the recent dynamic of patterns of self-perception in Belarusian society can be interpreted as the beginning of a gradual "heating" of the ethnocultural vitality of Belarusians, which is occurring under the impact of the agency of elites. Ethnolinguistic survival and vitality in this context can be viewed both as an argument in the struggle between different forces on the political arena and a factor contributing to victory in the rivalry between them. In this context, the phenomenon of "ethnic temperature" can be analysed not only from the perspective of its impact on group vitality and survival, but also as a phenomenon dependent on various political, cultural and historical factors.