High Quality Content by WIKIPEDIA articles! Generalmajor Herrmann Karl Robert "Henning" von Tresckow (January 10, 1901 – July 21, 1944) was a Major General in the German Wehrmacht who organized German resistance against Adolf Hitler. He attempted to assassinate Hitler in March 1943 and drafted the Valkyrie plan for a coup against the German government. He was described by the Gestapo as the "prime mover" and the "evil spirit" behind the July 20 plot to assassinate Hitler. He committed suicide on the Eastern Front upon the plot`s failure.