This came at the price of losing Moscow, whose population was evacuated. When Napoleon finally left Moscow Kutuzov blocked Napoleon's way through Kaluga into the richer, unspoilt southern regions of Russia in the Battle of Maloyaroslavets, ratio 1:1. Napoleon decided to avoid a decisive battle and marched via Mozhaisk to Smolensk into a higher probability of starvation, as it was the devastated route of his advance. The old general "escorted" Napoleon on the more southern roads but attacked him at the Battle of Vyazma, at the Battle of Krasnoi, ratio 1 French soldier to 1.4 Russian, and at the Battle of Berezina, ratio 1:1.75. In parallel Cossack bands and peasants assaulted isolated French units during their whole retreat. With Kutusov's strategy of attrition warfare, on 14 December the remainder of the French main army left Russia. The only remaining troops were the flanking forces (43,000 under Schwarzenberg, 23,000 under Macdonald), about 1,000 men of the Guard and about 40,000 stragglers, about 110,000, all that were left of the 612,000 (including reinforcements)that had entered Russia.