The French Revolutionary Wars (French: Guerres de la Révolution française) were a series of sweeping military conflicts resulting from the French Revolution that lasted from 1792 until 1802. They pitted France against Great Britain, Austria, Prussia, Russia, and several other countries. The wars are divided into two periods: the War of the First Coalition (1792–1797) and the War of the Second Coalition (1798–1802). Initially confined to Europe, the fighting gradually assumed a global dimension. After a decade of constant warfare and aggressive diplomacy, France had conquered territories in the Italian peninsula, the Low Countries, and the Rhineland with its very large and powerful military which had been totally mobilized for war against most of Europe with mass conscription of the vast French population. French success in these conflicts ensured military occupation and the spread of revolutionary principles over much of Europe.
As early as 1791, the other monarchies of Europe looked with outrage at the revolution and its upheavals; and they considered whether they should intervene, either in support of King Louis XVI to prevent the spread of revolution, or to take advantage of the chaos in France. Austria stationed significant troops on its French border and together with Prussia issued the Declaration of Pillnitz, which threatened severe consequences should anything happen to King Louis XVI and Queen Marie Antoinette. After Austria refused to recall its troops from the French border and to back down on the perceived threat of using force, France declared war on Austria and Prussia in the spring of 1792; both countries responded with a coordinated invasion that was turned back at the Battle of Valmy in September. This victory emboldened the National Convention to abolish the monarchy. A series of victories by the French Revolutionary Army abruptly ended with defeat at Neerwinden in the spring of 1793. The French suffered additional defeats in the remainder of the year, and these difficult times allowed the Jacobins to rise to power and impose the Reign of Terror to unify the nation.