Hans von Seeckt
Johannes Friedrich Hans von Seeckt was a German military officer who served as Chief of Staff to August von Mackensen, and was a central figure in planning the victories Mackensen achieved for Germany in the east during the First World War.
Seeckt was born in Schleswig onApril 1866 to an old Pomeranian family, which had been ennobled in the eighteenth century. Though the family had lost its estates, Seeckt was a thoroughgoing aristocrat and his father was an important general within the German Army, finishing his career as military governor of Posen. Seeckt followed his father into military service, joining the Army in 1885 at the age of 18. He served in the elite Kaiser Alexander Guard Grenadiers, then joined the Prussian General Staff in 1897. In 1913, Seeckt became the Chief of Staff of the III Corps based in Berlin.
Source: Wikipedia