Chiang Wei-kuo
Drewes was born on 20 October 1918 in Lobmachtersen, at the time in the district of Wolfenbüttel, present day a borough of Salzgitter. He was the son of pharmacist Wilhelm Drewes and his wife Margarete, née Hayder, and had an older sister Hanna and a younger sister Käthe. Drewes passed his "Abitur" (School Leaving Certificate) at the "" in Wolfenbüttel and joined the military service in the Army on 2 November 1937 as a "Fahnenjunker". He initially served with "Panzer-Regiment" 6, a regiment of the 3rd Panzer Division, in Neuruppin and was posted to the "Kriegsschule" in Munich on 15 November 1938 as a "Fähnrich". While stationed in Munich, Drewes befriended Chiang Wei-kuo, an adopted son of Republic of China President Chiang Kai-shek. In the Army, he commanded a PzKpfw I.