Joseph Stalin rose to power as a Communist leader of the Soviet Union, and forced obedience upon his people. He killed rivals and sent millions of "disloyal" people to labor camps.
Emperor Hirohito was the leader of Japan. Japan's military held great power and played a key role in setting an aggressive course for Japan.
Congress in the U.S. passed Neutrality Acts, banning selling weapons and making loans to nations at war.
In March 1939, Hitler epinvaded Poland, causing the start of World War II.