Hideki Tojo, a general of the Imperial Japanese Army, was Minister for War from 1940 to 1941 and Prime Minister of Japan from October 1941 to July 1944.
Tojo was best known for ordering the attack on Pearl Harbor (although planning for the action began in April 1941, long before he assumed office as Prime Minister).
While the criminality of the Pearl Harbor attack may be debated, Tojo was responsible for conducting a vicious war in Asia that took the lives of countless civilians and many Allied prisoners of war.
After a failed suicide attempt at the end of the war, Tojo was arrested, along with 25 “Class A” war criminals, and tried by an international tribunal of judges from eleven countries. The Tokyo trial lasted over two years. In December 1948 Tojo received the death sentence.
General Douglas MacArthur, Supreme Commander for the Allied Powers, declined to commute the death sentence and Tojo and six other defendants were hanged in the Sugamo Prison.
Other Prominent Japanese figures who were not prosecuted for war crimes included Emperor Hirohito and the notorious Ishii Shiro, who had carried out vicious human experimentation as head of Unit 731, Japan’s bacteriological and chemical warfare research facility in Manchuria. The Emperor was not prosecuted for political reasons. Presumably, the biological/chemical warfare expert was spared because the United States military wanted his knowledge for their own programs.