The research is based on the analysis of materials from the archive of the Polish Composers’ Union of the 1960s, which are being introduced into scientific circulation for the first time. It is emphasized that the cultural representation of Ukraine at the official level has always been carried out under the control of the Union of Composers of the USSR and in coordination with the ideological sector of the Communist Party of the Soviet Union, which was one of the mechanisms of colonial cultural enslavement of Ukraine. Based on archival documents, it is proved that Ukrainian music in the 1960s was not performed by Polish artistic groups, published or recorded in Poland. The only official channel for disseminating information about Ukrainian musical culture at that time was Polish Radio. Numerous facts of unofficial private cultural initiatives by conductor Ihor Blazhkov, composer Leonid Hrabovskyi, and other young Ukrainian musicians, which went against the official discourse of the state authorities and beyond the party and ideological control of Soviet Ukraine, have been established. It is proved that alternative unofficial channels of communication between Ukrainian artists and the Polish Composers’ Union vividly illustrate their desire to “break through the Iron Curtain”, receive direct information about modern trends in music and novelties in the festival and concert life of Europe, become the part of European and world cultural processes.