World War One hardly needed justification in post-war France (in the sense that it was somehow pointless or avoidable). In the decades leading up to 1914, revanche (revenge) for the German annexation of Alsace-Lorraine in 1871 dominated political discourse. To begin, I’ll give a crude breakdown of the events of 1871, how they influenced pre-war sentiments, and general feelings in the post-war period.

The Second French Empire, lead by Napoleon III, was a colonial juggernaut with holdings across the globe and second only to the British in imperial prestige. In an effort to preserve their continental supremacy in the face of a unifying Germany, war was declared on July 19th, 1870. In a mere 6 weeks, Napoleon was captured, forced to abdicate, and the newly formed Third Republic signed a treaty which saw them bequeath the provinces of Alsace and Lorraine to a newly formed German state. With defeat to the Germans fresh in their minds, French soldiers then were ordered to take up arms against their fellow countrymen in Paris, who had rejected the legitimacy of the Third Republic, and set out to establish a working class commune.

Lines had been drawn. On one side, those who embraced modernity, republicanism, and secularism. On the other, to quote Frederick Brown, “those who championed the restoration of throne and altar.” Explanations for why the French were defeated quickly turned into scapegoating, with Jews and republicanism being the main targets. Jews, as evident by the Dreyfus Affair, were charged with being agents of the Germans; determined to undermine French virtue. Republicans, as in the case of General Boulanger, were seen to be “soft” and unfit to govern the French people.

By 1914, French chauvinism had surged through the country. The right had dubbed Germany as France’s hereditary enemy. Karl Marx’s grandson, Jean Longuet, had called for Socialists to, “defend the France of the Revolution and of Democracy.” As such, political and social disagreements were pushed aside in favor of a Union Sacrée, an agreement between the various leftist factions both parliamentary and revolutionary and the government, that opposition to the Republic and strikes would be put on hold during the war. The center-right newspaper Le Figaro asserted that finally, “The French could now be French, imbued with common ideals of brotherhood, salvation, and sacrifice.”

The post-war period saw the far right heap praise upon those in the government they so often attacked (often through both words and actions). L’action Française editor, and avowed monarchist Leon Daudet, praise Poincare for, “honoring the most important part of the Treaty of Versailles.” There’s no doubt, that the re-annexation of Alsace-Lorraine was the part in question. Those on the left who had opined nonviolence in 1914, could only claim impotence in 1918. Ludovico-Oscar Frossard, summarized the antiwar left’s morose sentiment in at a union conference when he claimed that, “We did nothing, because we could do nothing.” For many however, German humiliation, of which the re-annexation was a part of, was all the justification needed for the war. Victory had restored French provincial holdings and re-established a sense international prestige. It is important to note, however, that victory over the Germans did not extinguish the reactionary flames that were lit in the years and decades after 1871. Anti-semitism, ethnic nationalism, and anti-parliamentarianism were just as prevalent, if not more so.

Sources: Frederick Brown - The Embrace of Unreason 1914-1940 and For the Soul of France: Culture Wars in the Age of Dreyfus