This article offers a new explanation for the sudden rise in popularity of French existentialism, in particular of Sartre’s version, in the mid-1940s. It develops a multidimensional account that recognizes both structural and cultural factors. The explanation differs from, and more fully addresses the complexity of the situation than, the two most prominent existing explanations: namely Anna Boschetti’s Bourdieu-inspired account and Randall Collins’s network-based approach. It is argued that, because of specific socio-political circumstances, the intellectual establishment became tainted and lost (...) legitimacy, with its aesthetic and philosophical views now regarded as outdated if not politically dangerous. This hiatus brought unprecedented publishing opportunities for a new philosophical current, and skilful public performances by the main protagonists helped its ascendancy. Most importantly, existentialist writers colluded with de Gaulle in portraying a cohesive and defiant French nation; and their philosophy, especially in its notion of responsibility, enabled sections of French society to assimilate and make sense of the recent past, whilst drawing a line underneath it so as to move forward. (shrink)