In the Russian Campaign, the Bavarian army suffered terrible losses - of about 33,000 men (including following reinforcements) who marched in 1812, only 4,000 returned. Pressed by the Crown Prince and General Wrede, King Maximilan I Josef turned with a heavy heart away from the French and changed to the Allied camp shortly before the Battle of Leipzig. The attempt by Wrede to stop the victory of the Grande Armée in 1813 at the Battle of Hanau ended in a narrow defeat for his Austro-Bavarian corps. The campaign of 1814 began badly for the Allies, but Wrede made up for his earlier defeat with valuable victories over his former allies at the battles of Arcis-sur-Aube and Bar-sur-Aube.