What is probably the best known and broadest conspiracy against the Nazi regime was headed by Claus Graf Schenk von Stauffenberg (1907–1944), who attempted to assassinate Hitler on July 20, 1944, and then led the subsequent, failed coup. Stauffenberg had initially supported the military goals of the Nazis, but when Hitler’s aggression and his methods of warfare came to light later in the 1930s, he shared in the increasing alienation felt by some other high-ranking Wehrmacht officers. Since the Gestapo and the Security Service (SD) of the SS could only penetrate the Wehrmacht to a limited extent, it was the only organization that had at its disposal the instruments of power for a potentially successful coup. Nonetheless, earlier attempts at assassination and sabotage that had come from various resistance groups within the Wehrmacht had failed. It would appear that only Germany’s imminent defeat prompted many of the co-conspirators, who were also recruited from the ranks of the police and the state administration, to engage in active resistance.

On Thursday, July 20, 1944, Stauffenberg, in his capacity as chief of staff to the Commander of the Reserve Army [Befehlshaber des Ersatzheeres, BDE], flew to a briefing at the Führer’s East Prussian headquarters, the Wolf’s Lair [Wolfsschanze]. He set off a bomb there and fled. On his way back to Berlin, Stauffenberg believed that the assassination attempt had been successful, but Hitler, in fact, had only been slightly injured. Thus, Stauffenberg was operating under the assumption that the coup would be completed according to the so-called Valkyrie Plan [Walküreplan], whereby the military would assume executive power and eliminate the party’s most important sources of power—the Gestapo, the SS, and the SD.

As the following proclamation by Stauffenberg reveals, the conspirators were hoping to blame Hitler’s assassination on a fictitious clique of party functionaries as a way of justifying the takeover of power by the Reserve Army. In the absence of official word about Hitler’s death, the follow-up actions of the co-conspirators were too slow and uncoordinated, and the attempted coup was quickly quashed by supporters of the regime. Stauffenberg was shot that same night. In the wake of the extensive Gestapo investigation, which lasted until the end of the war, about 1,500 people were imprisoned and 200 killed.