World War II
alsothe Second World War(1939-45) a war involving almost every major country in the world. On one side were the Allies (including the UK, France, and Poland, and after 1941 the US and the Soviet Union) and on the other side the Axis (including Germany, Japan, and Italy). The war was started by Adolf
Hitler, the
Nazi leader of Germany, who aimed to increase German power by attacking other countries and taking control of them. The war ended when Germany was defeated, and the US dropped
nuclear bombs on the Japanese cities of
Hiroshima and
Nagasaki. About 55 million people were killed in the war.