Erwin Planck

His father held a professorship at the Berlin Frederick William University since 1889 and had become a notable member of the German Physical Society (DPG); his children grew up in the wealthy environment of the Grunewald mansions colony.

Shortly after he came back to Germany, Kurt von Schleicher and his wife were shot at their Babelsberg home by members of the Sicherheitsdienst (SD) in the Night of the Long Knives on 30 June 1934.

In 1936, Planck changed career paths and went into business, becoming a leading employee at the Otto Wolff corporate group, a large conglomerate in Cologne.

In August 1939, on the eve of World War II, a group including Prussian Finance Minister Johannes Popitz, Planck, and Reichsbank president Hjalmar Schacht approached General Georg Thomas, head of the Defence Economy and Armament Office asking him to thwart the outbreak of the forthcoming Invasion of Poland.

In 1940, Planck, Popitz, Ulrich von Hassell and General Ludwig Beck drafted a "Provisional Constitution" on the assumption that the forthcoming attack on the Western Front would overthrow Hitler's regime.