German general and an expert on tanks. He supported blitzkrieg military tactics, and successfully used tanks to conquer Poland in 1939 and France in 1940. He was commander-in-chief of the Panzer tank forces of the German army, and won key victories in 1940 and 1941.
In spite of this, he was fired by Adolf Hitler after he disagreed with his order to hold firm against the Soviet counter-offensive in 1941-42 outside of Moscow.
In 1944 Guderian was appointed again as chief-of-staff to the German Army High Command, but was again fired in March 1945 because he recommended making peace with the Allies.