Between 1938 and 1944, the CIUP, which then had 19 international pavilions, went through a paradoxical phase in its history. Since the mid-1980s, the CIUP had been resonating with the radicalism of a mobilized and fragmented youth in a context of forced exile, shrinking international relations, and a global economic crisis that increased student migration (particularly scholars and students from Central and Eastern Europe). From 1940 onwards, the Wehrmacht requisitioned the CIUP, and the pavilions were closed, occupied, and degraded. In France, the advent of the Vichy regime provoked an ambivalent situation for the CIUP between clandestine resistance networks, anti-Semitic policies, and protection for a campus that partly corresponded to the ideology of the National Revolution; the dream of a student community, youth hygiene and national influence. This period reveals the fragility of international academic mobility in the face of dictatorships and global conflict. It also shows that transnational academic networks and long-term interpersonal links, such as private law foundations, are resources in their own right in times of peril.