We propose to analyse the activity and connectivity of the International Committee on Intellectual Cooperation (ICIC) of the League of Nations through a fine indexing of its correspondance archives. Created in 1922, this committee brought together leading scientists such as Henri Bergson, Albert Einstein, Marie Sklodowska-Curie and Hendrik Lorentz and laid the foundations of UNESCO after the Second World War. The rise and bureaucratization of this organization during the 1920s is accompanied by a rapid increase of the number of documents produced and received as well as a complexification of information flows. By mapping this circulation in a network composed of more than 3.000 individuals involved in intellectual cooperation during its early years (approx. 30.000 documents), this method reveals the main organizational trends while highlighting the situation of actors that are so far little studied in this context. This exploratory “datafication” of the archives of the League of Nations leads us to reconsider and recontextualize the personal commitment of the individuals who made up the ICIC.The development of a multilayer model that allows a comparison between the officialinstitutional framework of the international organizations of this time and the structuringof information exchanges at an individual level helps to highlight the discrepancy from a hierarchical level to another. In our example, we propose to use this multilayer model to flatten the hierarchical structure of the two upper levels so that they contain the individual nodes. Creating such a stable visualisation is the condition for a comparative analysis of the edges connecting groups in time of based on a thematic filtering of the data.