These essays provide an authoritative introduction to Carl von Clausewitz and enlarge the history of war by joining it to the history of ideas and institutions and linking it with intellectual biography. Reflecting Peter Paret's three decades of study of Clausewitz and of the history of war, they examine Clausewitz's theoretical work in the context of his time and in relation to war as a general historical phenomenon. Although the analytical strength of On War makes it far more than a historical document, Clausewitz's ideas and the methods he employed to express, develop, and test them become clearer when his work is seen against a historical background.