In the Napoleonic Wars, hard-fought battle 8 Feb 1807 as Napoleon tried to prevent a joint force of Prussians and Russians under Marshal Levin Benningsen retreating toward Königsberg (now Kaliningrad, Estonia) after their defeat at Pultusk. They made a stand at Eylau, East Prussia (now Znamensk, Russia), about 38 km/24 mi east of Königsberg. The battle took place in a snowstorm and both sides sustained heavy casualties.
Napoleon, with 79,000 troops in total against Benningsen's 73,000, attacked with two infantry corps and six divisions of cavalry, all the troops he had to hand since the rest of his army was still moving up. The attack was beaten back and was followed by a Russian counterattack; Napoleon countered this with his 7th corps which had now arrived on the scene. Blinded by snow, enfiladed by artillery, and attacked by infantry the 7th Corps broke and fled when a sudden charge of Russian cavalry descended upon them. As a final hope, Napoleon threw in 18,000 of General Joachim Murat's cavalry against the Russians, who were scattered, ridden down, and destroyed piecemeal. As more French troops arrived throughout the day, Napoleon pressed his attack against Benningsen, who retired into Königsberg, having lost 18,000 troops and 24 guns.