Napoleonic Wars (1803–15)
Campaigns by a series of European coalitions against French expansion under Napoleon I. In 1803, Britain declared war and formed the Third Coalition with Austria, Russia, and Sweden in 1804. Napoleon defeated the Austrians at Ulm, and the Russians and Austrians at Austerlitz (both 1805), but the British under Admiral Nelson won a decisive naval victory at Trafalgar (1805). Prussia joined the Fourth Coalition (1806) but was decisively defeated at Jena. Resistance to the French occupation of Portugal (1807) began the Peninsular War. In 1808, French troops were sent to quell a Spanish rebellion, but were faced by the British army led by the Duke of Wellington. The Fifth Coalition collapsed with the defeat of Austria at Wagram (1809). In 1812, Napoleon invaded Russia. Bitter winter forced his retreat from Moscow, and much of his army died of starvation, hypothermia or were killed by the pursuing Russian forces under Mikhail Kutuzov. The Sixth Coalition defeated Napoleon at Leipzig (October 1813). In March 1814, Allied forces entered Paris. While the coalition was negotiating at the Congress of Vienna, Napoleon escaped from exile in Elba and overthrew Louis XVIII. War renewed during the Hundred Days of Napoleon's return to power and ended in his final defeat at the Battle of Waterloo (June 1815).