France Declares War: The Revolutionary Wars Begin

The French National Assembly voted to declare war on the Habsburg King of Bohemia and Hungary on April 20, 1792, launching a conflict that would engulf Europe for the next twenty-three years. The declaration, passed with near-unanimous enthusiasm, reflected a revolutionary government drunk on its own rhetoric, convinced that the peoples of Europe would rise up to join France's crusade for liberty. Instead, the war nearly destroyed the revolution, consumed millions of lives, and eventually produced Napoleon Bonaparte. The immediate cause was Austrian and Prussian hostility toward revolutionary France. Emperor Leopold II and King Frederick William II had issued the Declaration of Pillnitz in August 1791, threatening intervention if the French royal family were harmed. French emigres, including aristocrats and army officers who had fled the revolution, lobbied openly for foreign invasion. The Girondins, the dominant faction in the Assembly, pushed for war partly to export the revolution and partly to expose Louis XVI as a traitor, calculating that he would be forced to choose between France and his Austrian-born wife's relatives. Louis XVI, for his part, secretly wanted the war too. He believed the French army, weakened by the emigration of its officer corps, would lose quickly, and that Austrian and Prussian troops would restore his authority. Both sides miscalculated. The initial French campaigns were disasters, with poorly led armies retreating in panic. But the threat of invasion radicalized the revolution. The storming of the Tuileries in August, the September Massacres, the abolition of the monarchy, and the execution of Louis XVI in January 1793 all followed from the pressures the war created. The conflict expanded steadily. Britain, Spain, the Netherlands, and most of the Italian states joined the coalition against France. French revolutionary armies, reorganized and supplied by mass conscription under the levee en masse, won stunning victories and conquered Belgium, the Rhineland, and northern Italy. The wars that began with the Assembly's vote on April 20, 1792, did not end until Waterloo in 1815. By then, an estimated five million people had died, borders across Europe had been redrawn, and the modern era of mass warfare and nationalist politics had arrived.