Anton Ludwig August von Mackensen (b. Dec. 6, 1849, Prussia-d. Nov. 8, 1945, Burghorn, Germany), German Field Marshal, began his military career as a volunteer in 1869 and served in the Franco-Prussian War, later formally entering the German Army in 1873. During World War I, he commanded the Ninth Army, Eleventh Army, and Army Group Kiev. He led campaigns against Serbia and Romania, and at the end of the War was captured and held prisoner until November 1919. He retired from the Army in 1920.
From the description of Mackensen, August von, 1849-1945 (U.S. National Archives and Records Administration). naId: 10574815