The Prussian general Gerhard Johann David von Scharnhorst (1755-1813) rebuilt the Prussian army after its collapse at Jena in 1806.

On Nov. 12, 1755, G. J. D. von Scharnhorst was born in Bordenau, the son of a former sergeant. In the Prussia of Frederick the Great his origins debarred him from an officer's career, so he took service as an artillery officer in the Hanoverian army, distinguishing himself by considerable valor in the war against revolutionary France. In 1801 he was able to transfer to the Prussian army, being appointed director of the military academy in Berlin. Two years later he was made a member of the general staff. In the campaign of 1806-1807 he served as a staff officer. He did so well in that capacity that, after the collapse, he was appointed minister of war, chief of the general staff, and head of the Military Reconstruction Commission.

Scharnhorst was convinced...