Pius XII and the German Resistance

During the Second World War, Pope Pius XII maintained links to the German Resistance to Nazism against Adolf Hitler's Nazi regime. Although remaining publicly neutral, Pius advised the British in 1940 of the readiness of certain German generals to overthrow Hitler if they could be assured of an honourable peace, offered assistance to the German resistance in the event of a coup and warned the Allies of the planned German invasion of the Low Countries in 1940. The Nazis considered that the Pope had engaged in acts equivalent to espionage.

The Army was the only organisation in Germany with the capacity to overthrow the government; from within it, a small number of officers came to present the most serious threat posed to the Nazi regime. The Foreign Office and the Abwehr (Military Intelligence) of the Oberkommando der Wehrmacht (Supreme Command of the Armed Forces) also provided vital support to the movement. Hitler's 1938 purge of the military was accompanied by increased militancy in the Nazification of Germany, a sharp intensification of the persecution of Jews, and daring foreign policy exploits, bringing Germany to the brink of war; it was at this time that the German Resistance emerged.

Pius XII assumed the papacy in 1939. In the buildup to war, he sought to act as a peace broker. As the Holy See had done during the pontificate of Benedict XV (1914–1922) during World War I, the Vatican, under Pius XII, pursued a policy of diplomatic neutrality through World War Two—Pius XII, like Benedict XV, described the position as "impartiality", rather than "neutrality." Pius XII's relations with the Axis and Allied forces may have been impartial, but early in the war he shared intelligence with the Allies about the German Resistance and the planned invasion of the Low Countries and lobbied Mussolini to stay neutral.

With Poland overrun but France and the Low Countries yet to be attacked, the German Resistance wanted the Pope's assistance in preparations for a coup to oust Hitler. Colonel Hans Oster, the deputy head of the German counterespionage bureau (Abwehr) was a key figure in the German military opposition to Hitler. He passed information to the Dutch of a planned invasion of the Low Countries in November 1939 and supported General Ludwig Beck in instructing Abwehr officer Josef Müller to go to Rome to warn the Allies, by the Pope, of the planned invasion. Müller was sent on the clandestine trip to Rome to seek papal assistance in the developing plot by the German military opposition to oust Hitler.

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