When Adolf Hitler rose to power in 1933, Witzleben was named to command the Berlin Military Area. He was promoted to brigadier general in February 1934 and major general that December. In 1935, he took command of III Corps. He was raised to lieutenant general in October 1936.
Witzleben became an opponent of Hitler as early as 1934 and an active conspirator in 1938 as a result of Hitler's purge of senior generals and Hitler's threat of war against Czechoslovakia. Witzleben commanded Army Group C in the September 1939 Polish Campaign. Promoted to Generaloberst (U.S. equiv. full general) that November, he commanded First Army in the 1940 Campaign for France. On 19 July 1940, Hitler named him a field marshal, and until March 1941, Witzleben commanded Army Group D. He then became Oberbefehlshaber West (commander in chief of the Army West) in France, but his attitude toward Hitler became known. In March 1942, Witzleben went on medical leave for an operation, and Hitler used this as an excuse to retire him on 21 March. He was never reemployed.
The bomb plot to assassinate Hitler was to be carried out on 20 July 1944, with Witzleben assuming the position of commander in chief of the armed forces thereafter. Witzleben, however, dallied, and when the plot failed, he was arrested and tried for treason by the Nazi People's Court. As the principal army officer among the accused, he was treated with special ridicule. Condemned to death on 8 August 1944, he was strangled by piano wire that same day. Robert T. Kaczowka
Mitcham, Samuel W., Jr. Hitler's Field Marshals. Chelsea, MI: Scarborough House, 1990.; Müller, Klaus-Jürgen. "Witzleben, Stülpnagel and Speidel." In Correlli Barnett, ed., Hitler's Generals, 43–72. New York: George Weidenfeld, 1989.
Robert T. Kaczowka