2. Napoleon's Invasion of Russia, 1812French emperor Napoleon Bonaparte is generally regarded as one of history's top military tacticians.
But 200 years ago, he committed a grave error by leading his Grande Armée—likely the largest European armed force ever assembled to that point—across the Niemen River into Russia.
Although it never lost a pitched battle there, the Grande Armée was almost completely wiped out within six months by freezing temperatures, food shortages, disease and Russian assaults.
This proved to be the beginning of the end for Napoleon, who was forced into exile in April 1814.