Page "Carl von Clausewitz" Paragraph 5

Clausewitz served during the Jena Campaign as aide-de-camp to Prince August.

At the Battle of Jena-Auerstedt on October 14, 1806 – when Napoleon invaded Prussia and defeated the massed Prussian-Saxon army commanded by Karl Wilhelm Ferdinand, Duke of Brunswick – he was captured, one of the 25, 000 prisoners captured that day as the Prussian army disintegrated.

He was 26.

Clausewitz was held prisoner in France from 1807 to 1808.

Returning to Prussia, he assisted in the reform of the Prussian army and state.