Michael Andreas Barclay de Tolly in the context of "French invasion of Russia"

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

Beginning on 24 June 1812, the initial wave of the multinational Grande Armée crossed the Neman River, marking the entry from the Duchy of Warsaw into Russia. Employing extensive forced marches, Napoleon rapidly advanced his army of nearly half a million individuals through Western Russia, encompassing present-day Belarus, in a bid to dismantle the disparate Russian forces led by Barclay de Tolly and Pyotr Bagration totaling approximately 180,000–220,000 soldiers at that juncture. Despite losing half of his men within six weeks due to extreme weather conditions, diseases and scarcity of provisions, Napoleon emerged victorious in the Battle of Smolensk. However, the Russian Army, now commanded by Mikhail Kutuzov, opted for a strategic retreat, employing attrition warfare against Napoleon compelling the invaders to rely on an inadequate supply system, incapable of sustaining their vast army in the field.