Field Marshal Hans Karl Freidrich Anton, count von Diebitsch (1785-1831) was a Prussian officer who served with the Russian army during the Napoleonic Wars and who eventually became chief of the Russian General Staff.
Diebitsch was the son of an ADC to Frederick the Great. Many Prussian officers entered the Russian service later in the Napoleonic Wars and especially after the defeats at Jena and Auerstadt in 1806, but Diebitsch made the switch much earlier in his carrier.
Diebitsch fought with the Russian army at Austerlitz (1805), where he was wounded. He recovered in time to take part in the drawn battle of Eylau (7-8 February 1807), and the costly French victory at Friedland (14 June 1807).
In 1812 he was promoted to major-general and served with Wittgenstein's army. He commanded Wittgenstein's advance guard during the pursuit of the retreating French. This brought him up against his fellow Prussians, then serving as reluctant allies of the French on their northern flanks. Diebitsch's men split the Prussians from their French allies, and he then helped negotiate the Convention of Tauroggen (30 December 1812) in which Yorck's Prussian Corps declared itself neutral. This was the first stage in bringing the Prussians out of the French alliance, and in February 1813 the Prussians joined the growing coalition against France.
Diebitsch took part in the 1813 campaign in Germany, performing well at Dresden and Leipzig. He was also involved in the invasion of France in 1814 where he was an advocate of an attack on Paris. He was also present at the Congress of Vienna.
After the Napoleonic Wars end Diebitsch continued to rise in rank, and his career survived the death of Tsar Alexander I in 1825. He remained influential under Tsar Nicholas, who later ennobled him. He became Chief of the Russian General Staff and was a successful commander during the Russo-Turkish War of 1828-29, where he replaced Wittgenstein as commander-in-chief. He most famous exploit was the Adrianople or Transbalkan campaign, which saw a Russian army reach Adrianople (now Edirne, just inside the small European part of modern Turkey). Diebitsch was given the honorary name 'Zabalkansky' in commemoration of his achievement (making him Count von Diebitsch-Zabalkansky).
In 1830 he was given command of the forces sent to suppress a revolt in the Congress Kingdom of Poland, but he died on 10 June 1831 before the revolt had been suppressed. The cause of death is unclear, with cholera or suicide both possible.