When Napoleon Bonaparte invaded Russia in June 1812, he commanded the largest army Europe had ever seen, numbering over 600,000 men. To support this massive force, the French military relied on tens of thousands of horses to pull heavy supply wagons, artillery, and officer carriages. However, the logistical strategy suffered from a fatal flaw: draft horses require massive amounts of high-calorie grain, specifically oats, to maintain the energy needed for heavy labor.
Unlike rugged native Russian ponies that could survive on scrub vegetation and bark, standard European workhorses required thousands of tons of oats daily. As the French army pushed deeper into Russian territory, the scorched-earth tactics employed by retreating Russian forces left the countryside devoid of harvested grain. Napoleon's supply train quickly outran its own logistics, leaving horses to forage on green rye and wet grass.
This poor diet caused severe dysentery and colic among the animals, killing tens of thousands of horses before the French even reached Moscow. Without draft horses, the army was forced to abandon thousands of supply wagons filled with rations, medicine, and winter gear along the roadside. When the bitter Russian winter set in and the retreat began, the remaining horses were slaughtered for meat or perished in the snow.
The supply train breakdown created a disastrous domino effect: stranded soldiers had no food, no spare boots, and no heavy transport for wounded troops or artillery. Ultimately, the humble oat, or rather the lack thereof, doomed Napoleon's grand conquest long before the temperatures dropped below zero.