The article examines and discusses the diplomatic activities and accomplishments of Jurgis Baltrušaitis, the long-standing envoy of Lithuania to the Soviet Union. The study is focused on several problematic moments of the envoy’s work in Moscow, especially the unique environment in which Baltrušaitis’s geopolitical views took shape and which later seemed to have influenced his diplomatic activities. The archival materials used in the article (they include Baltrušaitis’s political reports and his diplomatic correspondence) reveal the Lithuanian envoy’s controversial position regarding relations with the USSR. The study also discusses Baltrušaitis’s tense relations with the Ministry of Foreign Affairs and the reasons for the constant conflicts with the leadership of Lithuania, analyses the algorithms of the envoy’s communications with the Ministry of Foreign Affairs, and provides an assessment of the results of the ‘geopolitical mission’ that Jurgis Baltrušaitis aspired to achieve.