Austria's defeat at the battle of Hohenlinden, on 3 December 1800, created a power vacuum in the area now known as Germany, and Napoleon lost little time in transforming this zone into a pro-French 'cordon sanitaire', creating as he did so the Duchy of Berg, which he later united with Kleve. Like Kleve-Berg, Westfalia was also ruled entirely according to French law, and both provided troops for the French Emperor. In this first of five volumes concerning Napoleon's German allies, Otto Von Pivka explores the Napoleonic campaigns, uniforms, flags and standards of Westfalia and Kleve-Berg.