The First French Empire began to unravel in 1812, when he decided to invade Russia. Napoleon underestimated the difficulties his army would have to face whilst occupying Russia. Convinced that the Tsar was conspiring with his British enemies, Napoleon led an army of 600,000 soldiers to Moscow. He defeated the Russian army at Borodino before capturing Moscow, but the Tsar withdrew and Moscow was set ablaze, leaving Napoleon's vast army without adequate shelter or supplies. Napoleon ordered a retreat, but the bitter Russian winter and repeated Russian attacks whittled down his army, and only a battered remnant of 30,000 soldiers managed to limp back to French territory. The allies then continued a united effort against Napoleon until they had seized Paris forcing his abdication in 1814. His return to power the next year was resisted by all the allies and his army was defeated by a Prussian and Anglo-Allied force at Waterloo.