The new "Grande Armé"e was somewhat different from before; over one-third of its ranks were now filled by non-French conscripts coming from satellite states or countries allied to France. The behemoth force crossed the Niemen River on June 24, 1812, and Napoleon hoped that quick marching could place his men between the two main Russian armies, commanded by Generals Barclay de Tolly and Pyotr Bagration. However, the campaign was characterized by many frustrations, as the Russians succeeded no less than three times in evading Napoleon's pincers. A final stand for the defence of Moscow led to the massive Battle of Borodino on September 7, 1812. There the "Grande Armée" won a bloody but indecisive and arguably pyrrhic victory. A week after the battle, the "Grande Armée" finally entered Moscow only to find the city largely empty and ablaze. Its soldiers were now forced to deal with the fires while hunting down arsonists and guarding the city's historic districts. Napoleon and his army spent over a month in Moscow, vainly hoping that the Russian emperor would respond to the French peace offers. After these efforts failed, the French set out on October 19, now only a shadow of their former selves. The epic retreat over the famous Russian winter dominates popular conceptions of the war, even though over half of the "Grande Armée" had been lost during the summer. The French were harassed repeatedly by the converging Russian armies, Marshal Michel Ney even conducting a famous rearguard separation between his troops and the Russians, and by the time the Berezina was reached Napoleon only had about 49,000 troops and 40,000 stragglers of little military value. The resulting battle and the monumental work of General Jean Baptiste Eblé's engineers saved the remnants of the "Grande Armée". Napoleon left his men in order to reach Paris and address new military and political matters. Of the 685,000 men that constituted the initial invasion force, only 93,000 survived.