Napoleon thinking he could conquer Russia in 20 days

Napoleon invaded Russia in June of 1812 with about 600,000 men. Planning to end the war in 20 days, he only brought enough food for 30 days. This marked a turning point in the Napoleonic Wars. The Russians retreated and burned all of the crops in the process until winter came. Down to less than 100,000 cold and exhausted men, the French army was forced to abandon the campaign.