The article presents an overview of epistolary heritage and other documents of French thinker, diplomat, and writer Joseph de Maistre, which are stored in the Archive of Savoy (Chambery, France). The Savoy Archive is a major research center which contains in its personal provenance fonds correspondence, essays, notes, and dispatches of J. de Maistre. Chambery was the Savoy thinker’s hometown, a place where his personality and views were formed and where his complex life path began. The authors analyze the main problems that worried J. de Maistre and were reflected in his works and letters which may be found in the archive of Chambery. While working with archival documents, the authors used source studies methods: firstly, such general scientific methods as retrospective and analytical approach; secondly, comparative analyses; thirdly, source studies methods, such as critical and heuristic approach. These methods have allowed to analyze the epistolary legacy of J. de Maistre, to identify the yet unpublished sources and interpret them. All these documents help to reveal the circle of his Russian correspondents. The research allows to interpret the views of the French philosopher, one of the founders of political conservatism. The authors emphasize that it was in Russia that he created his main works that influenced the emerging Russian conservative socio-political thought. The study of archival fonds helps to determine his social circle while serving in Russia (1803-1817) as a Sardinian envoy. The analysis of these documents assesses his influence on the Russian political elite and Emperor Alexander I himself. These documents have great value for a number of reasons. Firstly, they allow to trace the evolution of Joseph de Maistre`s views, his career, social and political activities; secondly, they reflect the Russo-French relations in one of most crucial periods of the European history, that of the Napoleonic wars. The authors point out that formation and evolution of Napoleon Bonaparte's image in Russia was closely connected with the name of Joseph de Maistre. Thus, it is important to study the heritage of the French emigrants, the French at the Russian Emperor’s serve or on a diplomatic mission in St. Petersburg. Studying de Maistre’s views allows not only to monitor his ideological attitudes and their evolution, but also to identify the mechanisms of their adoption in Russia. The accumulated scientific material allows the authors to come to certain conclusions, which are valuable for studying not just J. de Maistre’s views and influence, but also Russo-French relations in the Napoleonic era. Thus, the analysis of archival materials of the J. de Maistre`s fond significantly expands our understanding of international relations in early 19th century, interaction of two cultures, history of the Russian socio-political thought.