The authors of this article, based on archival documents, analyzed the process of transformation of the Colombian left in the 1920s. They studied the first links established between the communist section of that country and the Comintern, paying special attention to the figure of Sylvestre Savitsky, one of the most mysterious figures in the history of the Latin American left. It shows the influence of the headquarters of the Third International and the emissaries of the Communist International, the Red Trade Union International and the Workers Party of America in the transformation of the Revolutionary Socialist Party into the Communist Party.