How did nationalism affect France during WW1

French nationalism emerged from its numerous wars with England, which involved the reconquest of the territories that made up France. The wars produced a great icon of French nationalism, Joan of Arc. The Catholic religion also played a major role after the Protestant Reformation.[2] French nationalism became a powerful movement after the French Revolution in 1789. Napoleon Bonaparte promoted French nationalism based upon the ideals of the French Revolution such as the idea of "liberty, equality, fraternity" and justified French expansionism and French military campaigns on the claim that France had the right to spread the enlightened ideals of the French Revolution across Europe, and also to expand France into its so-called "natural borders." Napoleon's invasions of other nations had the effect of spreading the concept of nationalism outside France.

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they believed democracy was worth the fight