Meanwhile, the one continental European power that was completely outside of his control was Russia. Despite the obvious problem of staging a full-scale invasion - Russia was far from France, it was absolutely enormous, and it remained militarily powerful - Napoleon concluded that it had come time to expand his empire's borders even further. In this, he not only saw Russia as the last remaining major power on the continent that opposed him, but he hoped to regain lost inertia and popularity. His ultimate goal was to conquer not just Russia, but the European part (i.e. Greece and the Balkans) of the Ottoman Empire. He hoped to eventually control Constantinople and the Black Sea, thereby re-creating most of the ancient Roman Empire, this time under French rule. To do so, he gathered an enormous army, 600,000 strong, and in the summer of 1812 it marched for Russia.
Napoleon faced problems even before the army left, however. Most of his best troops were fighting in Spain, and more than half of the "Grand Army" created to invade Russia was recruited from non-French territories, mostly in Italy and Germany. Likewise, many of the recruits were just that: new recruits with insufficient training and no military background. He chased the Russian army east, fighting two actual battles (the second of which, the Battle of Borodino in August of 1812, was extremely bloody), but never pinning the Russians down or receiving the anticipated negotiations from the Tsar for surrender. When the French arrived in Moscow in September, they found it abandoned and largely burned by the retreating Russians, who refused to engage in the "final battle" Napoleon always sought. As the first snowflakes started falling, the French held out for another month, but by October Napoleon was forced to concede that he had to turn back as supplies began running low.
The French retreat was a horrendous debacle. The Russians attacked weak points in the French line and ambushed them at river crossings, disease swept through the ranks of the malnourished French troops, and the weather got steadily worse. Tens of thousands starved outright, desertion was ubiquitous, and of the 600,000 who had set out for Russia, only 40,000 returned to France. In contrast to regular battles, in which most lost soldiers could be accounted for as either captured by the enemy or wounded, but not dead, at least 400,000 men lost their lives in the Russian campaign. In the aftermath of this colossal defeat, the anti-French coalition of Austria, Prussia, Britain, and Russia reformed.
Amazingly, Napoleon succeeded in raising still more armies, and France fought on for two more years. Increasingly, however, the French were losing, the coalition armies now trained and equipped along French lines and anticipating French strategy. In April of 1814, as coalition forces closed in, Napoleon finally abdicated. He even attempted suicide, drinking the poison he had carried for years in case of capture, but the poison was mostly inert from its age and it merely sickened him (after his recovery, his self-confidence quickly returned). Fearing that his execution would make him a martyr to the French, the coalition’s leadership opted to exile him instead, and he was sent to a manor on the small Mediterranean island of Elba, near his native Corsica.
He stayed less than a year. In March of 1815, bored and restless, Napoleon escaped and returned to France. The anti-Napoleonic coalition had restored the Bourbons to the throne in the person of the unpopular Louis XVIII, younger brother of the executed Louis XVI, and when a French force sent to capture Napoleon instead defected to him, the coalition realized that they had not really won. Napoleon managed to scrape together one more army, but was finally defeated by a coalition force of British and Prussian soldiers in June of 1815 at the Battle of Waterloo. Napoleon was imprisoned on the cold, miserable island of Saint Helena in the South Atlantic, where he finally died in 1821 after composing his memoirs.