English abstract (full article is in French):
Even before the end of World War I, conversations attempting to imagine a post-war Europe were taking place. In this article we will focus on a particular aspect of these conversations in regard to a new Europe: the desire expressed in many texts to achieve a natural and scientific reorganization of the continent, with the underlying conviction that with each state in its legitimate place, such a reorganization would necessarily lead to a lasting peace. In order to bring about this perfect map of Europe, many looked initially to earlier romantic and naturalist conceptions of linguistics. However, at the beginning of the twentieth century, romantic and naturalist ideas of language were contradicted and supplanted by a social conception of language. It is therefore necessary to examine why these outmoded ideas made their return at this particular moment in European history.