The main goal of this article is to reconstruct the encounter between Marxism and the labor movement in Argentina at the end of the 19th and the beginning of the 20th century. It is based on a case study of the local socialist weekly La Vanguardia, from its appearance in April 1894 until its conversion into a daily at the end of 1905. Based on an exhaustive analysis of more than 500 issues of the journal, I constructed a list of all those articles that reproduced content originally created in other countries, as well as a list of the brochures and books offered for sale. The specific goal is to provide a clearer and more precise idea of what texts and authors Argentine socialists read and published at the turn of the century. The opponents of Argentine socialism used to accuse it of being an ‘exotic flower’that simply imported European ideas. This idea spread in Argentine historiographic common sense, which reinforces the importance of developing empirical studies. How much of the material published in La Vanguardia actually came from foreign authors? From which countries and publications did they take more articles? Which authors were published the most? Which were the most repeated topics? What brochures were sold at the time? Where had they been published? These are some of the questions I intend to answer in this paper, drawing upon the data collected in my research.