How did Napoleon defeat Russia at the Battle of Friedland?

At the Battle of Friedland on June 14, 1807, Napoleon defeated the Russian army under Gen. Leonty Leontyevich Bennigsen by exploiting the Russians' vulnerable position against the Alle River.12

Bennigsen made a critical error by halting his forces at Friedland, where they became cramped in a narrow area between the river and the Posthenen millstream. While Marshals Jean Lannes and Édouard Mortier held the Russian center and right, Napoleon concentrated his forces and launched his main attack against the Russian left.2

The decisive moment occurred in the late afternoon when Michel Ney led an assault supported by a heavy artillery barrage. When the Russian defense faltered, the French artillery general Alexandre Sénarmont moved his guns to close range, using canister and grapeshot to devastate the congested Russian infantry. The resulting collapse forced the Russians into a chaotic retreat across the river, leading to approximately 19,000 Russian casualties and ultimately securing a French victory that led to the Treaties of Tilsit.2