The research is based on two concepts: 1) a stable ethnic name (ethnonym) testifies to the strong ethno-identity of people, and changes in this name indicate changes in ethnic selfconsciousness of the group; 2) the name of the language used by the ethnos (linguonym), as well as the ethnonym, is very significant for ethnic identity, and a stable linguonym and its formation is more important for the mentality of people than intra-linguistic changes. The purpose of the article is to show the stages of the formation of the names of Belarusians and the Belarusian language. This goal cannot be realized without referring to the formation of the ethnic identity of Belarusians. Since the diachronic approach is adopted, the necessary historical-geographical and linguistic context is given. The study applies methods of working with text: both with scientific literature and with original texts in the field of issues. The information from these two types of sources is used to show the stages of the formation of Belarusian ethnonyms and linguonyms. The synthesis and final interpretation were also carried out through the extralinguistic (first of all, historical) perspective. The formation of the names of the concept of “homeland” was also considered. As a result of the research, the author comes to conclusion that at the beginning of the 20th century Belarusians had already formed the names of their homeland, ethnos and language, that is, for more than a hundred years they considered themselves a separate nation.