The article is devoted to the process of displaying a changing historical discourse in a museum exposition. As an example, the author takes the case of the exposition building at the State Museum of Ethnography in 1930s — 1950s. Sources for research were archival materials of the Russian Ethnographic Museum. In the 1930s — 1950s. one of the most important policy areas of the USSR was to strengthen and develop its influence in the Slavic states. The territories of Western Ukraine and Western Belarus, which were part of Poland, entered the USSR in 1939. The State Museum of Ethnography, as a museum reflecting the national policy of the country, reacted to these events instantly: already in the autumn of 1939 an exhibition was being built that was supposed to form a correct perception of events for visitors. The process of accession was submitted through the prism of saving the fraternal people from enemy Poland. After the Second World War, the political mood, and with them, and science, and museums — are changing. So, the ideas of the Slavic brotherhood and the leading role of the Russian people in it become relevant. SME is building a series of exhibitions devoted to the folk art of the Slavs already in 1945. And in 1953, the 300th anniversary of the reunification of Ukraine and Russia was celebrated in the USSR, and a large, diverse exhibition at the SME would also be held. The author seeks to show how, in a changing political discourse, scientific discourse changed, and with it the museum space, how it was possible to form completely different political statements using the same museum objects.