Battle of Heilsberg

On 24 May 1807, the Siege of Danzig ended when Prussian General Friedrich Adolf, Count von Kalckreuth capitulated to French Marshal François Joseph Lefebvre. With Danzig secured, Napoleon was now free to turn against Bennigsen's army. Yet it was the Russian who struck first when he ordered his columns to converge on Marshal Michel Ney's exposed VI Corps on 2 June. Outnumbered 63,000 to 17,000, Ney fought a rear guard action at the Battle of Guttstadt-Deppen on 5 and 6 June. Though he lost his baggage train, two guns, and 2,042 men, Ney managed to escape to the southwest over the Pasłęka River with the bulk of his soldiers, leaving Bennigsen and his officers upset over the missed opportunity.

Within two days, Napoleon ordered his 190,000-man army to close in on the 100,000 Russians and 15,000 Prussians. Detecting the approaching avalanche, Bennigsen ordered his troops to retreat on Lidzbark Warmiński . The Russian army took up strong defensive positions around the town, which stood on the Łyna River. The French army, under Marshals Murat and Lannes, attacked on 10 June. Bennigsen repelled several attacks, resulting in huge French casualties, but had to withdraw towards Friedland the following day. Four days later, the decisive Battle of Friedland occurred, ending the War of the Fourth Coalition with the passing of the Treaty of Tilsit.

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