In the 1940s, under the combined impact of war, occupation, liberation, and cold war, a series of new departures in the realm of theology, party politics and apostolic missions left a profound imprint on European Catholicism. One of the products of this period of ebullience in European Catholicism was “Christian progressivism,” a tendency arising among the multiple branches of a fledgling Left Catholicism, then in its prime. Christian progressivism emerged out of the creative confluence of Catholic social movements and the communist experience. Nowhere in Western Europe was this phenomenon as prominent as in France.