Article is devoted to the native of Bassarabia, one of the founder of scientific Sovietology in Russian emigration, to talented publicist Simeon Osipovich Portujgejs (1880-1944). It is emphasized, that is the fullest its scientific potential reveals in works where the essence of the Bolshevism and its evolution from the Soviet Russia is analyzed. The article is considered the features of outlook and S.O.Portujgejs` political insight. The special attention is given the analysis of approaches and assessments by the Sovietologist of the problems connected with its attitude to Bolshevik revolution, with revealing contradictions of the Bolshevism, with disclosing a role of average layers and youth in revolution, with the attitude of the Bolshevism and economy, with evolution of communist party and the Soviet society. The forecast of the future of Russia is given, the historical sense of the Bolshevism reveals. It is emphasized, that S.O.Portujgejs` basic political predictions for evolution of the Bolshevism have proved to be true also conclusions of the Sovietologist remain actual and nowadays.