After their catastrophic defeat at the Battle of Jena-Auerstedt on 14 October, the Prussian armies fled north to the Elbe River with Emperor Napoleon I of France's victorious army in hot pursuit. The Prussians crossed the Elbe near Magdeburg and marched northeast, trying to reach safety behind the Oder River. Part of Napoleon's army thrust east to seize Berlin, while the rest followed the retreating Prussians. From Berlin, Murat moved north with his cavalry, trying to head off Hohenlohe.