We must be careful to present French society on the eve of the Great War as irreducibly divided between the rights, nationalists, who wanted war at all costs, and the left, internationalists, even antipatriotic, who, in turn, sought to prevent it with all means, even at the expense of the defense of the fatherland. For the majority of the French at the time, at the bottom of their mentality existed, in fact, a “defensive patriotism”, which was opposed to an offensive war, but which nevertheless recognized the need to defend the country when it suffered an aggression. During the July crisis, which brought all European powers to war, France was not a main actor, whose role was not at all decisive in its outbreak. However, it was by the decision of the French government that France entered the war, although the international situation did not leave it much room for maneuver. As the war approached, the feeling of being attacked by the German “invaders” intensified the patriotism of the French, then determined to fight against Germany which had attacked their “peaceful” homeland. Socialists and syndicalists, once firmly opposed to war, also ended up joining the “Sacred Union” for the defense of the invaded homeland, thereby demonstrating their patriotism. This “defensive” patriotism, however, could easily evolve into offensive violence. August 1, 1914 marked not only the mobilization of forces, but also the mobilization of minds. After the conscripts left for the front, the fight against the “internal enemies” began at the rear. The nascent “culture of war” brutalized the society.