The French, having invested Glogau, Breslau, and Graudentz, and left detachments to urge these sieges, moved towards the Polish frontier. General Bennigsen, with a considerable Russian army, had advanced to overawe the dissatisfied population, and was now at Warsaw. But the march of the French van, under Murat, soon alarmed him in these quarters. After some skirmishes of little moment the Russians retired behind the Vistula, and Murat took possession of the Polish metropolis on the 28th of November. On the 25th Napoleon himself had reached Posen, and found himself surrounded by a population in a high state of excitement and enthusiasm. The ancient national dress reappeared: hope and exultation beamed in every countenance; the old nobles, quitting the solitary castles in which they had been lamenting over the downfall of Poland, crowded the levees of the Victor, and addressed him in language which recalled the half-oriental character and manners of their nation. "We adore you," said the Palatine of Gnesna, "and with confidence repose in you all our hopes, as upon him who raises empires and destroys them, and humbles the proud—the regenerator of our country, the legislator of the universe." "Already," said the President of the Council of Justice, "already our country is saved, for we adore in your person the most just and the most profound Solon. We commit our fate into your hands, and implore the protection of the most august Cæsar."

Having largely recruited his armies with brave Poles, who fancied him both a Solon and Cæsar, Napoleon now moved forwards. General Bennigsen found himself under the necessity of abandoning first the line of the Vistula, and then that of the Bug, and, the French still advancing in numbers not to be resisted by his division, at length threw himself behind the river Wkra, where Kaminskoy, the Russian commander-in-chief, and three other divisions of the army, had by this time taken their ground. On the 23rd of December Napoleon reached and crossed the Wkra, and Kaminskoy ordered his whole army to fall back upon the line of the Niemen. Bennigsen accordingly retired towards Pultusk, Galitzin upon Golymin, both followed by great bodies of the French, and both sustaining with imperturbable patience and gallantry the severity of a march through probably the very worst roads in Europe, and of frequent skirmishes with their pursuers. But the minor divisions of D'Anrep and Bexhouden retreated without keeping up the requisite communications with either Bennigsen or Galitzin, and consequently suffered considerably, though the matter was grossly exaggerated in the French bulletins.

Bennigsen, in spite of Kaminskoy's orders to retreat at all hazards, made a stand, and a most gallant one at Pultusk. Having his left in that town, and his right on a wood, the general conceived his position to be too favourable for speedy abandonment, and on the 26th of December expected the onset of Lannes, Davoust, and the imperial guard of France. They charged with their usual impetuosity, and drove the Russian right wing, under General Barclay de Tolly, out of the wood; but Bennigsen skilfully availed himself of this occurrence; by his orders Barclay de Tolly retired much further than was necessary for his own safety, and the French, advancing unguardedly, found themselves confronted on very unfavourable ground with the Russian main body, which had now been arranged on a new line of battle, and of a battery of 120 guns, placed so as to command their march with terrible efficacy. The result was that the Russians lost 5000 in killed and wounded, the French 8000—one of their wounded being Marshal Lannes himself; and the French drew back from the hardly contested field with such haste, that all next day the advancing Cossacks sought in vain for their rear-guard. On the same day, and with nearly as much success, Prince Galitzin halted also, and awaited and repelled his pursuers at Golymin; and had either Bennigsen or Galitzin been supported by the other divisions which were doing nothing within a few miles of their respective marches, these events might have been improved so as to involve the French army in great and immediate perplexity. But in truth, the total want of plan and combination on the part of Kaminskoy was by this time apparent to the veriest tyro in his camp. Symptoms of actual insanity appeared shortly afterwards, and the chief command was transferred, with universal approbation, to Bennigsen.

The affairs of Pultusk and Golymin, however, were productive of excellent effects. They raised to a high pitch the spirits of the Russian soldiery; and they afforded Napoleon such a specimen of the character of his new enemy, that instead of pursuing the campaign, as he had announced in his bulletins, he thought fit to retire, and place his troops in winter quarters. He himself took up his residence at Warsaw, and the army occupied cantonments in various towns to the eastward.

But General Bennigsen, having proved at Pultusk what Russian troops could do when under a determined commander, no sooner found himself at the head of an army of nearly 100,000 men, than he resolved to disturb the French in their quarters, and at all events give them such occupation as might enable the King of Prussia to revictual Konigsberg, where the few troops, gathered round that unfortunate sovereign, were already beginning to suffer many privations. With this view Bennigsen advanced as far as Mohrungen, where the French sustained considerable damage in a skirmish, and from whence his Cossacks spread themselves abroad over the country—creating such confusion, that the leaguer of Konigsberg being for the moment relaxed, the Prussian garrison received welcome supplies of all kinds, and Napoleon himself perceived the necessity of breaking up his cantonments, and once more concentrating the army for active war.

His design was to occupy Willensberg, to the rear of the great Russian camp at Mohrungen; thus cutting off the new enemy's communications with his own means of resource, in the same manner which had proved so fatal to the Austrians at Ulm, and the Prussians at Jena. But Bennigsen, having learned the plan from an intercepted despatch, immediately countermarched his army with masterly skill, and thus involved Napoleon in a long series of manœuvres, not to be executed in such a country at that dismal season without the extremity of hardship. The Russians themselves, inured as they were to northern climates, and incapable of even dreaming that a soldier could seek safety in flight, were reduced to the border of frenzy by the privations of these long marches. Their commissariat was wretched: the soldiers had often no food, except such frozen roots as they could dig out of the ground; and, tortured with toil and famine, they at length demanded battle so vehemently, that, against his own judgment, General Bennigsen consented to grant the prayer. He selected the town of Preuss-Eylau, and a strong position behind it, as his field of battle; and—after two skirmishes, one at Landsberg, the other nearer the chosen ground, in the former of which the French, in the latter the Russians, had the advantage,—the whole army reached Preuss-Eylau on the 7th of February.

In the confusion of so great a movement, a division designed by Bennigsen to occupy the town itself, misunderstood the order, and evacuated it at the approach of the enemy's van. The French took possession of the place accordingly, and—General Bennigsen commanding it to be regained, as soon as he learned the mistake that had occurred—the whole day was spent in severe fighting within the town, which was taken and retaken several times, and at the fall of night remained in the hands of the French. On either side the loss had been very great, and Napoleon coming up in person, perceived that the contest must needs be renewed at daybreak. The night was clear, and he could trace the enemy's line darkening the whole of an admirably selected position, between which and the dearly contested town, a level space covered with snow, and two or three small frozen lakes, glittered in the mingled light of an unclouded moon and innumerable watch-fires.

The great battle of PREUSS-EYLAU was fought on the 8th of February. At dawn of day the French charged at two different points in strong columns, and were unable to shake the iron steadiness of the infantry, while the Russian horse, and especially the Cossacks under their gallant Hetman Platoff, made fearful execution on each division, as successively they drew back from their vain attempt. A fierce storm arose at mid-day: the snow drifted right in the eyes of the Russians; the village of Serpallen, on their left, caught fire, and the smoke also rolled dense upon them. Davoust skilfully availed himself of the opportunity, and turned their flank so rapidly, that Serpallen was lost, and the left wing compelled to wheel backwards so as to form almost at right angles with the rest of the line. The Prussian corps of L'Estocq, a small but determined fragment of the campaign of Jena, appeared at this critical moment in the rear of the Russian left; and, charging with such gallantry as had in former times been expected from the soldiery of the Great Frederick, drove back Davoust and restored the Russian line. The action continued for many hours along the whole line—the French attacked boldly, the Russians driving them back with unfailing resolution. Ney, and a fresh division, at length came up, and succeeded in occupying the village of Schloditten, on the road to Konigsberg. To regain this, and thereby recover the means of communicating with the King of Prussia, was deemed necessary; and it was carried accordingly at the point of the bayonet. This was at ten o'clock at night. So ended the longest and by far the severest battle in which Buonaparte had as yet been engaged. The French are supposed to have had 90,000 men under arms at its commencement; the Russians not more than 60,000. After fourteen hours of fighting, either army occupied the same position as in the morning. Twelve of Napoleon's eagles were in the hands of Bennigsen, and the field between was covered with 50,000 corpses, of whom at least half were French.

Either leader claimed the victory; Bennigsen exhibiting as proof of his success the twelve eagles which his army, admitted to be inferior in numbers, bore off the field: Buonaparte, that he kept possession of the field, while the enemy retired, the very night after the battle, from Eylau towards Konigsberg. It was, in truth, a drawn battle; and to have found an equal was sufficient bitterness to Napoleon. The Russian general-in-chief had retreated, in opposition to the opinion of most of his council, out of anxiety for the personal safety of the King of Prussia at Konigsberg, and desire to recruit his army ere another great action should be hazarded. The French, triumphant as was the language of their bulletins, made no effort to pursue. Bennigsen conducted his army in perfect order to Konigsberg, and the Cossacks issuing from that city continued for more than a week to waste the country according to their pleasure, without any show of opposition from the French. But the best proof how severely Napoleon had felt the struggle of Preuss-Eylau, is to be found in a communication which he made to Frederick William, on the 13th of February, five days after the battle, offering him, in effect, the complete, or nearly complete restoration of his dominions, provided he would accept of a separate peace: with the king's answer; namely, that it was impossible for him to enter on any treaty unless the Czar were a party in it. Finally, on the 19th of February, Napoleon left Eylau, and retreated with his whole army on the Vistula; satisfied that it would be fatal rashness to engage in another campaign in Poland, while several fortified towns, and, above all, Dantzick, held out in his rear; and determined to have possession of these places, and to summon new forces from France, ere he should again meet in the field such an enemy as the Russian had proved to be.

Dantzick was defended with the more desperate resolution, because it was expected that, as soon as the season permitted, an English fleet and army would certainly be sent to its relief. But the besiegers having a prodigious superiority of numbers, and conducting the siege with every advantage of skill, the place was at length compelled to surrender, on the 7th of May; after which event, Napoleon's extraordinary exertions in hurrying supplies from France, Switzerland and the Rhine country, and the addition of the division of 25,000, which had captured Dantzick, enabled him to take the field again at the head of not less than 280,000 men. The Russian general also had done what was in his power to recruit his army during this interval; but his utmost zeal could effect no more than bringing his muster up again to its original point—90,000; the chief blame lying, as it was alleged, with the coldness of the English cabinet, who, instead of lavishing gold on the Emperor of Russia, as had been done in other similar cases, were with difficulty persuaded to grant him at this critical time, so small a supply as £80,000. Russia has men to any amount at her command; but the poverty of the national purse renders it at all times very difficult for her to maintain a large army in a distant contest.