The Battle of Smolensk was the first major battle of the French invasion of Russia. It took place on 16–18 August 1812 and involved about 45,000 men of the Grande Armée under Emperor Napoleon I against about 30,000 Russian troops under General Barclay de Tolly. Napoleon occupied Smolensk by driving out Prince Pyotr Bagration's Second Army. The French artillery bombardment burned the city to the ground. Of 2,250 buildings, 84% were destroyed with only 350 surviving intact. Of the city's 15,000 inhabitants, about 1,000 were left at the end of the battle inside the smoking ruins. With over 15,000 casualties, it was one of the bloodiest battles of the invasion.

The French invasion of Russia, also known as the Russian campaign and in Russia as the Patriotic War of 1812, was initiated by Napoleon with the aim of compelling the Russian Empire to comply with the continental blockade of the United Kingdom. Widely studied, Napoleon's incursion into Russia stands as a focal point in military history, recognized as among the most devastating military endeavors globally. In a span of fewer than six months, the campaign exacted a staggering toll, claiming the lives of nearly a million soldiers and civilians.