Carl von Clausewitz 
On War 

Vom Kriege is a book on war and military strategy by Prussian general Carl von Clausewitz (1780–1831), written mostly after the Napoleonic wars, between 1816 and 1830, and published posthumously by his wife Marie von Brühl in 1832.
It has been translated into English several times as On War. On War is an unfinished work. Clausewitz had set about revising his accumulated manuscripts in 1827, but did not live to finish the task. His wife edited his collected works and published them between 1832 and 1835.

Carl Philipp Gottfried von Clausewitz (1 June 1780 – 16 November 1831) was a Prussian general and military theorist who stressed the "moral" (meaning, in modern terms, psychological) and political aspects of war. His most notable work, Vom Kriege (On War), was unfinished at his death. Clausewitz was a realist in many different senses and, while in some respects a romantic, also drew heavily on the rationalist ideas of the European Enlightenment.

TRANSLATED BY COLONEL J.J. GRAHAM