Correspondence of the foreign delegation of the socialist-revolutionaries party with the party center in Soviet Russia (1921-1925) as a historical source

The article considers the correspondence of emigrants with the party center in Soviet Russia in 1920-1925 as a historical source. These materials are currently almost unknown to researchers and have not been introduced into scientific circulation. The purpose of the article is to describe the state of the problem research, key documentary publications and research by Russian and foreign authors. The importance of secret correspondence is noted as a source due to the availability of information that is not reflected in other materials. Systematic correspondence with overseas Socialist party centers in Russia began in 1921, the most active correspondence was in 1921-1922, 1923, while later the intensity of correspondence reduced. The greatest attention in correspondence was paid to cooperation of party work in Russia and in emigration, the press, quantity and geography of local subordinated organizations in Soviet Russia, program and tactical questions of the Socialists-Revolutionaries. The most discussed topics in 1922-1923, were the trial of leaders of Socialist-Revolutionaries in Moscow, the protection of foreign SRS defendants and counter-propaganda campaigns in European countries. Finally, the correspondence contains interesting information about the conflicts within the Bolshevik leadership, and the daily life of the population of Soviet Russia during the NEP period. The correspondence of the foreign delegation of the SR party with the leading party centers of Soviet Russia is a valuable and diverse historical source. These materials significantly complement our understanding of the Socialists-Revolutionaries in the first half of the 1920s. In addition, they contain important information about the political and socio-economic situation in Soviet Russia during this period.