Classic example - Napoleon made a major misstep when he declared war on Russia after a dispute with Tsar Alexander I and launched an invasion of Russia in 1812 with 600,000 troops, twice the number of the standing Russian army. The campaign was a catastrophe. Obstinant Russian resistance combined with the bitterly cold Russian winter dealt Napoleon a disastrous defeat, from which more than 95% of his invading force perished. 

Is this a neutral analysis? No. Is the analysis of Napoleon's campaign necessary here? No. Leave it to the relevant article - this is a summary of Russia's history.