ENThe article deals with the role of sport in building and maintaining national identity in difficult ethnopolitical conditions. It deals with the history of Lithuania in the twentieth century, where relations between Lithuanians and Poles living in the area were primarily determined by the Polish-Lithuanian dispute over the belonging of the Vilnius region in the interwar period. The different sporting traditions contributed to the preservation of the national identity of both nations during the period of Soviet enslavement, while the sporting successes of Lithuanians in 1947–1988, especially of basketball players on teams representing the Soviet Union, were an element of their political emancipation. It led, together with other factors, to the restoration of Lithuanian independence and, at the same time, conditioned the need to redefine relations between Lithuanians and Poles in Lithuania. In this process, sports usually played a role in bringing the two communities together. The figure of Michał Sienkiewicz evidences this, a sportsman, later an extremely active sportsman for Poles in the Vilnius region, a participant in sports life during Soviet times, including an athletics judge at the legendary pole vaulting competition with Władysław Kozakiewicz at the XXII Olympics in Moscow in 1980. During the period of building the foundations of Lithuanian independence, he initiated and participated in the reconstruction of the Lithuanian National Olympic Committee and the Polish Gymnastic Association "Sokół" in Lithuania. Keywords: sport, politics, history of Lithuania, history of sport, Lithuania, Vilnius Region, Poles in Lithuania, basketball. [From the publication]