The Napoleonic Wars were a sequence of armed struggles between France, ruled by Napoleon, and coalitions of European nations governed by absolute monarchies whose objectives were the defeat of Napoleon and the restoration of the French monarchy under the Bourbons. Being a continuation of the French Revolutionary Wars (1792-1802), the Napoleonic Wars began in 1803 when Great Britain declared war on France after the implementation of the Treaty of Amiens had failed. This immediately led to the War of the Third Coalition (1803-1806), whose important military phases included the Ulm Campaign, pitting France against Austria; the Battle of Austerlitz, in which Napoleon decisively defeated the Russo-Austrian Army; and the Italian Campaign with the invasion of Naples.
Until 1808, Napoleon had always come out victorious, but when he took the decision to invade Spain his problems began as the English-Spanish armies and guerrillas in the Iberian Peninsula would prove the his Grande Armée (Great Army) could be beaten. The Napoleonic Wars took a turn for the worst in 1812, when Napoleon Bonaparte initiated the Russian Campaign which turned out to be a complete military failure as he lost more than 450,000 men, frozen to death in the severe Russian winter conditions, or killed by Russian cossacks. Napoleon was forced to abdicate for the first time after his defeat in the Battle of Leipzig (1813) during the War of the Sixth Coalition and was exiled to the island of Elba in the Mediterranean. However, he escaped from the island and returned to the continent to begin his Hundred Days Campaign. Nevertheless, his new army was composed mostly of inexperienced and lightly trained troops as most of the best and fine French soldiers and officers had been killed in past battles, especially during the Russian Campaign. The last battle of the Napoleonic Wars was the Battle of Waterloo in 1815, in which the French General was thoroughly defeated by the Seventh Coalition forces under the command of the Duke of Wellington.
The Napoleonic Wars had a deep impact on the future political and military development in Europe. Having invaded Austria and Germany, destroying the Holly Roman Empire of the Germanic Nation, an Old Order, Napoleon created great resentment in the German people as his armies committed a lot of abuses. This caused the emergence of German Romanticism, and romanticism in Germany was nationalism. Also, the defeat of Napoleon and the bankruptcy of France by years of war, meant the rise of Great Britain as a new empire, exerting political hegemony in the world for more than a century.