the name prior to 1946 of the city of Bagrationovsk, Kaliningrad Olast, RSFSR.
During the Russo-Prusso-French War of 1806–07 a battle took place between Russian and French forces near Preussisch Eylau on Jan. 26–27 (Feb. 7–8), 1807. On January 4 (16) the Russian Army, under the command of General L. L. Bennigsen, mounted an offensive westward from Biala with the objective of crushing the isolated left-flank corps of M. Ney and J. Bernadotte of the Napoleonic army. Owing to Bennigsen’s indecisiveness, the offensive was unsuccessful. Napoleon assembled up to 70,000 troops from their winter quarters and went over to the offensive, moving north from Allenstein (now Olsztyn) with the objective of cutting off the Russian Army (78,000 men, including 8,000 Prussians) from Russia. Covered by General P. I. Bagration’s rear guard, the main forces of the Russian Army withdrew to a position northeast of Preussisch Eylau, where a bloody two-day battle ensued. Napoleon’s attempt to envelop the left wing of the Russian forces was stopped by their stubborn defense. Each side lost 26,000–36,000 men. Combat operations lasted until May 1807.