He was forced into realy retirement after he critized Adolf Hitler's persecution of Werner von Fisch, and the Night of the Long Knives.
At the start of the Second World War he was recalled, and placed in charge of the 1st Army, which tasked with invading France in May 1940. He then became a Field Marshal. In 1942, after Operation Barbarossa, he was again critical of the government, and was retired again. In 1944 he was arrested for involvement in Claus von Stauffenberg's plot to kill Hitler, and was executed on August 8.