The Invasion of Russia, 1812

By 1811 relations between Napoleon and Alexander I had broken down over the Continental System, Poland and rival ambitions. In June 1812 Napoleon crossed the Niemen with a Grande Armée of around 600,000 men, about half of them from allied and conquered states. The Russians retreated, avoiding a decisive battle and leaving devastated land. At Borodino on 7 September both sides suffered enormous losses, and Napoleon entered Moscow a week later, only to find it largely abandoned; fires soon destroyed much of the city. The tsar refused to negotiate.

In October Napoleon began a retreat that turned into catastrophe through hunger, cold, disease and constant attack, including a desperate crossing of the Berezina River in November. Only a small fraction of the army returned. Historians stress that most losses came from disease, hunger and desertion before winter, not only from the cold.