Carl Von Clausewitz was a Prussian soldier and German military theorist who stressed the moral and political aspects of war. He entered the Prussian army in 1792. Clausewitz became one of the leaders of Prussian army reform, but later resigned from the Prussian army and entered Russian service.
Clausewitz distinguished himself as a Russian staff officer. After several successful campaigns, he returned to Prussian service, and served as chief of staff of an army corps during the Waterloo campaign. In 1818, he became a general and was appointed administrative head of the War College.
During the next 12 years, Clausewitz used much of the leisure that this position provided in writing his historical studies and his major work on strategy, ‘On War’. It is on this that his fame rests. He left his imprint on German military thought, and became known as a ‘philosopher of war’.