Battle of Eylau - Prelude

Prelude

With the Prussian army reduced to a handful of harried fugitives after Jena-Auerstedt, Napoléon occupied the major cities of Germany and marched on east in pursuit of the remaining forces opposed to him. These were largely Russians under the command of the frail 68-year-old Field Marshal Mikhail Kamensky. The old marshal was unwilling to risk battle, and continued to retreat, leaving the Grande Armée free to enter Poland almost unopposed. Nevertheless, as the French pressed aggressively eastward across the Vistula, they found the Russians defending the line of the Wkra River. The French seized a crossing over the Wkra on 23 December at the Battle of Czarnowo. Russian resistance soon stiffened and on 26 December the two armies clashed at the Battles of Pułtusk and Gołymin. After these fierce engagements Napoléon's troops took up winter quarters in Poland to recuperate after a victorious but exhausting campaign.

In January 1807, the new Russian army commander Levin August, Count von Bennigsen attempted to surprise the French left wing by shifting the bulk of his army north from Nowogród to East Prussia. Incorporating a Prussian corps on his right flank, he first bumped into elements of the VI Corps of Marshal Michel Ney, who had disobeyed his emperor's orders and advanced far north of his assigned winter cantonments. Having cleared Ney's troops out of the way, the Russians rolled down on the isolated French I Corps under Marshal Jean-Baptiste Bernadotte. Tough fighting at the Battle of Mohrungen allowed Bernadotte's corps to escape serious damage and pull back to the southwest. With his customary inventiveness, Napoléon saw an opportunity to turn the situation to his own advantage. He instructed Bernadotte to withdraw before Bennigsen's forces, and ordered the balance of the Grande Armée to strike northward. This maneuver might envelop the Russian army's left flank and cut off its retreat to the east. By a stroke of luck, a band of Cossacks captured a messenger carrying Napoleon's plans to Bernadotte and quickly forwarded the information to General Pyotr Bagration. At once Bernadotte was left unawares and a forewarned Bennigsen immediately ordered a retreat east to Jonkowo to avoid the trap.

As Bennigsen hurriedly assembled his army at Jonkowo, elements of Marshal Nicolas Soult's IV Corps reached a position on his left rear on 3 February. That day, General of Division Jean François Leval clashed with Lieutenant General Nikolay Kamensky's 14th Division at Bergfried (Berkweda) on the Alle (Łyna) River, which flows roughly northward in the area. The French reported 306 casualties while claiming to inflict 1,100 on their adversaries. After seizing Allenstein (Olsztyn), Soult moved north on the east bank of the Alle. Meanwhile, Napoleon threatened Bennigsen from the south with Marshal Pierre Augereau's VII Corps and Ney's troops. Kamensky held the west bank with four Russian battalions and three Prussian artillery batteries. After an initial attack on Bergfried was driven back, the French captured the village and bridge. A Russian counterattack briefly recaptured the bridge. That night, the French remained in possession of the field and Soult claimed that he found 800 Russian dead on the field. Marching at night, Bennigsen retreated directly north to Wolfsdorf (Wilczowo) on the 4th. The next day he fell back to the northeast, reaching Burgerswalde on the road to Landsberg (Górowo Iławeckie).

By early February the Russian army was in full retreat relentlessly pursued by the French. After several aborted attempts to stand and fight Bennigsen resolved to retreat to the town of Preussisch-Eylau and there make a stand. During the pursuit, perhaps influenced by the dreadful state of the Polish roads, the savage winter weather and the relative ease with which his forces had dealt with Prussia, Napoléon had allowed the Grande Armée to become more spread out than was his custom. In contrast, Bennigsen's forces were already concentrated.