Guderian had developed motorized tactics in the pre-war army, while keeping himself well-educated about armored formations in other armies. In particular, he implemented the use of radio communication between tank crews and devised shock tactics that proved highly effective. In May 1940, he commanded the Panzer divisions that overwhelmed the French defences at Sedan, France, leading to the surrender of France a month later. After the German defeat at the Battle of Moscow in December 1941 he was transferred to reserve.
After the defeat at Stalingrad in early 1943, Hitler appointed him to a new position, rebuilding the Panzer forces, but he bickered with many other generals, who managed to get his duties re-allocated. He was then appointed Chief of the General Staff of the Army in July 1944, but this was largely a symbolic role since Hitler had effectively become his own Chief of Staff. Guderian was dismissed in March 1945. From 1945 to 1948, Guderian was held in U.S. custody, but released without charge. He later served as an advisor overseeing the establishment of the military in West Germany. Guderian died in 1954.