Hans Walter Zech‐Nenntwich was born on 10 July 1916, in Thorn, Prussia, German Empire[2] He became a member of the Nazi Party before 1933 and joined the SA.

[2] Zech-Nenntwich was transferred from Sachsenhausen to the Mauthausen concentration camp and his unit there was later reorganized into the SS Heimwehr Danzig.

From 1939 to 1940, he received training courses at the SS-Junkerschule Bad Tölz and served in the SS-Totenkopfverbände as a non-commissioned officer in Poland.

[2] In 1941, he was transferred to the 2nd SS Cavalry Regiment where he served as a reconnaissance officer during the invasion of the Soviet Union.

From 1942 to 1943, he served in the 8th SS Cavalry Division Florian Geyer until he was transferred back to Warsaw after suffering an injury.

[7] The West German government attempted to extradite him from Egypt, but President Gamal Abdel Nasser refused.