This article is a first approach into how the African continent was integrated in networks of knowledge. Wefocus on methods of exchange and constitution of knowledge, and seek to distinguish the role of the various categories of actors, both European and African. These networks were organized step by step starting from the contributions of travellers, local intermediaries and around the development of learned societies whose activities could be encouraged or initiated by the states. Europeans, in their will to know new resources, encountered various difficulties - which were gradually overcome - on the material and technical aspects. While others, cultural, religious and political, were creating problems to have access to the local knowledg...