Lasalle went into immediate action at the Battle of Austerlitz, with the 1st Dragoon Division, under the command of Divisional General Louis Klein, in the Cavalry Reserve of Marshal Joachim Murat. Because of his successes on the field, he was given command of a Light Cavalry Brigade consisting of the 5th and 7th Hussar Regiments, also under the command of Marshal Murat. Lasalle's star was high during the 1806 campaign for Prussia, where his hussars became known as the "Brigade Infernale" ("Hellish Brigade"), with Colonels François Xavier de Schwarz and Ferdinand-Daniel Marx as his regimental commanders.