In 1806 Gneisenau served as one of Prince Hohenlohe's staff-officers, fought at Saalfeld (10 October 1806) and Jena (14 October 1806), and a little later commanded a provisional infantry brigade which fought under L'Estocq in the Lithuanian campaign. Early in 1807, the Prussian Army sent Major von Gneisenau as commandant to Kolberg, which, though small and ill-protected, with the additional assistance of Schill and Nettelbeck succeeded in holding out against Napoleonic forces until the Peace of Tilsit of July 1807. The commandant received the highly prized "Pour le Mérite" and promotion to lieutenant-colonel.