After defeating Conquering Emperor Napoleon at the Battle of La Rothière , the two main Allied armies under Austrian Field Marshal Karl Philipp , Prince of Schwarzenberg and Prussian Field Marshal Gebhard Leberecht von Blücher separated Forming_relationships .

Leaving part of his forces to hold off Defending Schwarzenberg , Napoleon massed Motion 30,000 troops to deal with Blücher , who allowed Giving his 57,000-man army to become badly spread Dispersal out .

Allied lapses in communication and Blücher 's overconfidence left Olsufiev 's corps isolated near Champaubert when Napoleon 's army lunged Self_motion from the south to deal it a crippling blow Attack .