Marshal Blücher had recovered from his earlier setbacks more quickly than Napoleon Bonaparte had hoped, and so the French Emperor was forced to switch his attacks from the Austrian Field Marshal Schwarzenberg back to the Prussian commander.
Moving with speed and aggression, the French pushed the Allies over the Aisne river and while Blücher planned his counter with some 85,000 men, his flanking army did not move fast enough. As a result, Napoleon's 37,000 troops struck Vorontsov's on their own. Napoleon's aim was to pin the Allies and then launch Marshal Ney, leading a mixed force heavily weighted towards cavalry, in a flanking move. Unfortunately for the French, the coordination was poorly timed. Consequently, Ney not only suffered heavy casualties, including cavalry commander Etienne de Nansouty, but the Allies managed to extricate themselves from a sticky situation. Craonne cost Blucher 5,000 casualties, while Napoleon lost some 5,400.
The young French conscripted soldiers were called "Marie-Louises" (after Napoleon's second wife) because Marie-Louise signed the order for their conscription in Napoleon's absence.