Participation in the battles of Ligny and Wavre had a deep influence on von Clausewitz's understanding of the strategic Arcanum. In both those battles Prussian Army was greatly outnumbered and overwhelmed by French forces, and was eventually forced into the retreat. Nevertheless, those battles were hollow victories for the French and major strategic victories for Prussians because they delayed Napoleon long enough to prevent reinforcements at Waterloo.
In 1818 von Clausewitz was promoted to Major-General and appointed as a director of the War College in Berlin. He remained at this prestigious post until year 1830 spending his time on research, teaching and writing his scholarly treatises. In 1830 he became Chief of Staff of the Prussian Army. This promotion coincided with an impromptu mobilization of Prussian forces which were rushed to the eastern borders of the Prussian Kingdom. The hasty mobilization and sealing-off Prussian borders was done in an anticipation of possible outbreak of violence - related to a turbulent political situation in the Russian Empire. While staying with his troops von Clausewitz contracted cholera and died in the city of on November 16, 1831. He was buried in his native city of Burg.
Von Clausewitz saw himself as a modern "scientist". Yet he ridiculed the popular thesis, attributed to Jomini, that one can create a "science of war."