At the outbreak of World War I in August 1914, Eichhorn was incapacitated because of an accident in May 1914, but he was able to play a part in the First Battle of Champagne, also known as the Battle of Soissons, at the beginning of 1915.[2] He became the commanding general of the 10th Army on 21 January 1915, and commanded it until 5 March 1918.[6] Under his command, the 10th Army engaged in the Second Battle of the Masurian Lakes in East Prussia in February 1915. In August 1915, he took Kovno and afterwards the fortresses of Grodno and Olita, and continued his advance into Russia.[2] He received the Pour le Mérite on 18 August 1915 and the oak leaves to the Pour le Mérite on 28 September 1915.[7] On 30 July 1916, while remaining in command of the 10th Army, Eichhorn became supreme commander of Army Group Eichhorn (Heeresgruppe Eichhorn) based around 10th Army, which he commanded until 31 March 1918.[8] On 18 December 1917, Eichhorn was promoted to Generalfeldmarschall (field marshal). On 3 April 1918, he became supreme commander of Army Group Kyiv (Heeresgruppe Kiew) and simultaneously military governor of Ukraine.[9]
Grave of Hermann von Eichhorn (1918) in the Invalidenfriedhof, Berlin
Death
Eichhorn was assassinated in Kyiv by a member of the Russian Party of Left Socialist-Revolutionaries, Boris Donskoy, who threw a bomb at the carriage carrying Eichhorn. At that time, Skoropadsky was walking nearby, he almost immediately came to the scene of the explosion and saw that the field marshal had no legs.[10] Also killed was Eichhorn's adjutant, Walter von Dreßer. Donskoy was convicted of murder by a field military court and executed by hanging.
^The philosopher Schelling was his maternal grandfather - Bickel, Otto (1938). Preussisch-deutsche Feldmarschälle und Grossadmirale [Prussian/German Field Marshals and Grand Admirals] (in German). Safari-Verlag. p. 262. Retrieved 27 May 2022. Er war mit einer Tochter des großen Philosophen Schelling verheiratet, und diese Julia von Eichhorn war eine durch Geist und Unmut gleichermaßen ausgezeichnete Frau. Ihr Sohn Hermann, der Fahnenjunker von Königgräß [...].