In 2025, the centenary of the founding of the International Lenin School (ILS)-the principal educational institution of the Comintern, responsible for training cadres for communist parties worldwide-will be commemorated. Despite its historical significance, the activities of the ILS remain insufficiently explored in historiography. However, researchers today have access to documents from the collections of the International Lenin School at the Russian State Archive of Socio-Political History (RGASPI), as well as records from the organisational structures of the Comintern, including protocols of the Politburo and commissions of the Executive Committee of the Comintern. These sources offer valuable insights into the establishment of the ILS, the evolution of its curriculum, shifts in its training objectives, and the development of its personnel. The primary aim of this study is to examine the creation of the ILS within the broader context of Comintern activities and the leadership of the All-Union Communist Party (Bolsheviks) in 1925. Specifically, it seeks to analyse the decisions made by party and Comintern leaders regarding the establishment of the school, their interactions, the role of key historical figures, the selection and composition of the teaching staff, and the principles guiding the recruitment of the first students. Although the ILS was undeniably a Comintern project, it was simultaneously developed within the framework of the Soviet system of communist universities and party cadre training. The study demonstrates that the ILS was regarded as the Comintern’s foremost educational institution, staffed by leading educators appointed by Soviet party structures. Moreover, its establishment was directly facilitated by the AUCP(B), which provided financial, methodological, and personnel support, as well as oversight of its curriculum and organisational structure.