Napoleon, seeing the whole course of the battle clearly, laid a trap for him. He withdrew Nansouty from the battle, and ordered Ricard, in command of his extreme left, to retreat slowly, fighting as if defeated. Sacken, as he saw the wavering on his right, threw his heaviest battalions and regiments upon that point, and attacked with headlong impetuosity. At the same time he had enough men left to keep Friant busy and in check. Napoleon, seeing the success of his ruse, suddenly brought up the Guard. He threw it around the right flank of Friant, and Sacken's left immediately began to give way. Ricard stopped his retreat suddenly and stood like a stone wall. His withdrawing Eagles moved forward. The advance of the Russian right stopped also, the Muscovite officers and soldiers were greatly amazed by the sudden resistance of an enemy retreating a moment since. One division of the Guard moved out to the support of Friant, who also advanced. The other division joined Mortier, who was in a hot fight with Yorck's cavalry and light infantry. Napoleon now turned to General Maurice, who had ridden up in advance of his horsemen.

"There"—he pointed down the hill toward the dark masses of the Russian right—"there's your chance, General."

The Comte de Vivonne needed but the word. Turning in his saddle he raised his sword. His cavalry had been waiting with unconcealed impatience during the morning. Eagerly they responded to the command. Dashing down the hill they fell on the puzzled Russian infantry around Épine-aux-Bois. Ricard's men opened to give them way. What had been a triumphant advance was turned into a retreat. The retreat bade fair to be a disaster, but the Russians, as has been noted, were splendid defensive soldiers. They formed squares. Although regiment after regiment had been ridden over and beaten to pieces, those who remained fought stubbornly.

Sacken perceived now that his only hope was to effect a junction with Yorck. He withdrew his men under cover of his artillery to Vieux-Maisons, and began to lead them by the left flank, at the same time sending frantic messages to Yorck, imploring him to hasten. But Yorck's guns were mired. He had only the teams attached to them. He could get no other horses. He was unaccountably delayed. He had faced about at the sound of the firing, but the movements of his main body were slow, deliberate. Nansouty, who had opened the battle, was now sent in by Napoleon to deliver the coup-de-grâce. With characteristic gallantry he fell upon the Russian columns.

Sacken was driven from the field. In killed, wounded, and prisoners he had lost half his force and all of his guns. His troops streamed westward through roads and woods in wild confusion. He would have been annihilated then and there but for the arrival of Yorck. The Prussian at last fell on Mortier's weak corps and the Guard on the northern road. Mortier's men were outnumbered four to one. They made a desperate resistance, but it was not until Napoleon ordered up the other division of the Guard, which had only been lightly engaged, and Maurice's cavalry, that Yorck's advance was checked.

The short day had drawn to a close. Preparations were made to pass the night on the field and in the town. All of Sacken's baggage train and provisions had fallen into Napoleon's hands. Montmirail had been a more decisive victory than Champaubert. Twenty thousand men had been eliminated from calculations for the time being. Sending couriers to Macdonald to move down the banks of the Marne with all possible speed, to get in the rear of Yorck, with whom he purposed to deal on the morrow, Napoleon, in high spirits, made preparations for the next day's battle.

The next morning, the thirteenth, leaving a heavy force to check any possible attack by Sacken, who had, with incredible energy and labor, partially at least reorganized his shattered troops, but who was too weak to do anything more than lead them away from any possible touch with Napoleon's troops, the Emperor advanced toward the little village of Château-Thierry. Yorck, by this time, had learned the full details of the disaster to Sacken. Indeed, several of Sacken's brigades had joined him, considerably augmenting his force. But he was now no match for Napoleon. To stay meant annihilation. He hastily made his disposition for a rear guard defense and a withdrawal. He made a stubborn rear guard battle of it during the day, and, although he lost heavily in men, guns and supplies, he finally succeeded in crossing the Marne and breaking the bridges behind him.

Macdonald had moved tardily. If he had shown half the enterprise of the Emperor he would have been at the crossing of the Marne in good time and Yorck would have been caught in a trap whence he could not have extricated himself. As it was, Napoleon added largely to the number of prisoners taken and the number of enemies killed. Altogether he had put twenty-five thousand men out of action, in killed, wounded and prisoners. He had taken one hundred and twenty guns—so many that he had to tumble them into the creeks and rivers, because he could not transport them all. He had rearmed and reclothed and provided for his gallant little army at the expense of the enemy. It was an exploit of which even he could be proud. On the other hand, in these operations the French had lost some four thousand men killed and wounded, and, as their army was so small, they could ill afford such a diminution of their forces.

Meantime, Blücher, apprised of these disasters, and at last awakened to his peril, bravely marched westward. He had come in touch with Marmont, and had driven him out of Champaubert after a desperate resistance. The day after the elimination of Yorck, the fourteenth, Napoleon headed his tired but triumphant troops back over the road to Champaubert, sending word to Marmont to hold the Prussians in check as long as possible, to dispute every rod of the way, but not to throw away his precious men or bring on a general engagement until the Emperor arrived.

The morning after that Napoleon fell on Blücher, who clearly outnumbered the French. But the allies were dismayed and disheartened. The name of the Emperor whom they had defeated and driven across Europe was again full of terror to them. The French were accordingly elated. They would not be denied. Marmont's men, intoxicated with the news of the success of the other divisions of the army, just as soon as they were given the word, which was just as soon as Napoleon could bring up their comrades, fell on Blücher like a storm. They came in battle contact in the village of Vauchamps. The fighting was of the most desperate character. The battle was harder than all of the others put together. Bavarians, Prussians, and Russians, fighting under the eye of brave old Blücher himself, who recklessly exposed his person on the field, were tenacious and courageous to the highest degree, but the tactics and dispositions of Napoleon, the spirit of his men, his own equally reckless exposure of his person under fire, and a cavalry dash at the allied rear at Janvilliers, finally turned the wavering tide of battle. The allies began to retreat, the French followed.