Russian Winter

[3][4] Russians call these muddy conditions rasputitsa, which occur with autumnal rains and spring thaws in Russia and make transport over unimproved roads difficult.

He notes that Napoleon's army was already suffering significant attrition before winter, owing to lack of supplies, disease, desertions and casualties of war.

[7] According to Chew in 1981, the main body of Napoleon's Grande Armée, initially at least 378,000 strong, "diminished by half during the first eight weeks of his invasion, before the major battle of the campaign.

This decrease was partly due to garrisoning supply centres, but disease, desertions, and casualties sustained in various minor actions caused thousands of losses.

At the Battle of Borodino, about 110 km from Moscow, on 7 September 1812—the only major engagement fought in Russia—Napoleon could muster no more than 135,000 troops and he lost at least 30,000 of them to gain a narrow and pyrrhic victory almost 600 miles inside hostile territory.

The sequels were his uncontested and self-defeating occupation of Moscow and his humiliating retreat, which began on 19 October, before the first severe frosts later that month and the first snow on 5 November.

[8] In fact his eastern army suffered more than 734,000 casualties (about 23% of its average strength of 3,200,000) during the first five months of the invasion before the winter started in recently occupied Poland and Soviet Belarus, Ukraine, and western Russia.