Carl von Clausewitz

Carl Philipp Gottlieb von Clausewitz (1 July 1780 – 16 November 1831) was a Prussian officer and military thinker who emphasized the psychological and political dimensions of war. His unfinished work *On War* is regarded as a foundational text in military strategy.

Clausewitz argued that war involves many interacting factors, and that commanders must make quick decisions amid the confusion, fear, and incomplete information he called the "fog of war." He believed history should check abstract theories that ignore real experience. Unlike Antoine-Henri Jomini, he thought war could not be reduced to maps or mathematics. One of his best-known sayings is, "War is the continuation of policy with other means."

His name appears in various forms. He wrote his first name with a "C" to align with classical tradition; "Karl" is sometimes used to stress his German identity. His tombstone reads "Carl Philipp Gottfried," but *Encyclopædia Britannica* uses "Gottlieb" based on older sources. Some modern scholars consider the tombstone more reliable than handwritten birth records.

Born in Burg bei Magdeburg, he was the youngest of four sons in a family that claimed noble status, though scholars doubt the connection. His grandfather was a theology professor; his father, a former lieutenant under Frederick the Great, worked in Prussian tax collection.

Clausewitz joined the Prussian army at age twelve as a lance corporal and rose to major general. He fought in the Rhine campaigns (1793–1794), including the siege of Mainz, and in the Napoleonic Wars from 1806 to 1815. In 1801 he entered the Kriegsakademie in Berlin, likely studied Kant, Fichte, and Schleiermacher, and gained the respect of General Gerhard von Scharnhorst. Along with Hermann von Boyen and Karl von Grolman, he helped reform the Prussian army between 1807 and 1814.

During the Jena Campaign, he served as aide-de-camp to Prince August. At the Battle of Jena-Auerstedt in 1806, he was captured and held prisoner in France until 1808. After returning to Prussia, he assisted in army and state reforms. In 1809 he wrote an anonymous letter to Johann Gottlieb Fichte about Fichte's work on Machiavelli.

On 10 December 1810, he married Countess Marie von Brühl, whom he had met in 1803. She came from an old noble family and moved in Berlin’s elite circles. Well-educated and politically connected, she supported his career and intellectual work, and later edited and published his collected writings.

Opposing Prussia’s forced alliance with Napoleon, Clausewitz left the Prussian army and served in the Imperial Russian Army from 1812 to 1813. He fought at the Battle of Borodino and helped negotiate the Convention of Tauroggen, which paved the way for the coalition that defeated Napoleon. In 1813 he joined the Russian–German Legion. In 1815, when the legion merged into the Prussian Army, he returned as a colonel and became chief-of-staff of Johann von Thielmann’s III Corps, serving at the Battles of Ligny and Wavre during the Waterloo campaign.