Abstract: The subject of the study is the process of formation of the Soviet federal socio-territorial space in the period 1917 – 1922, which includes the design of the state borders of Soviet Russia, the definition of the principles of the Soviet Federation (internationalism, the right of nations to self-determination), the regions composition of the RSFSR, the order of distribution of rigions and powers between the center and the regions, the scope of such powers and subjects of reference. The purpose of this study was to study the trends in the formation of the Soviet Federation in the diversity of its regions, the influence of these trends on outsiders of the next historical level of the Soviet Federation – the Union of Soviet Socialist Republics. To achieve this goal, a set of universal (dialectics), general scientific (analysis, synthesis, deduction, induction, structural-system method), private scientific methods (historical method), special methods (formal legal, comparative legal) were used. The novelty of the research lies in the fact that the author highlights the following trends in the first experiments of building a Soviet federal state: 1) the experimental nature of the construction of the Soviet federation in the absence of appropriate political and legal experience; 2) the ideocratic nature of the Soviet federal state, based on internationalism and the right of nations to self-determination; 3) the national-territorial nature with obvious asymmetry in favor of national subjects; 4) the initial non-determination of the borders of the Soviet federation; 5) the indefinite subject composition of the federation, constantly changing, both qualitatively and quantitatively; 6) the situational and individual nature of the distribution of subjects of competence and powers between the center and the regions. A special contribution of the author to the research of the topic is the introduction into scientific circulation of archival documents from the funds of the State Archive of the Russian Federation and the State Archive of Socio-Political History.