Who helped Hans-Ulrich von Oertzen develop Operation Valkyrie?
Hans-Ulrich von Oertzen: Born in Berlin to an aristocratic family, Oertzen followed his father into the army and trained as a general staff officer. Hans-Ulrich von Oertzen:  He then helped Claus von Stauffenberg to develop Operation Valkyrie. Operation Valkyrie: Operation Valkyrie (German: "Unternehmen Walküre" ) was a German World War II emergency continuity of government operations plan issued to the Territorial Reserve Army of Germany to execute and implement in case of a general breakdown in civil order of the nation.
Claus von Stauffenberg