Why is the year 1940 important?

give a couple of sentences as to why its important

 Major News Stories include Germany and Italy gain control of most of Western Europe, Winston Churchill becomes Prime Minister and inspires British People With speaches including "We Shall Fight Them On The Beaches, Dunkirk evacuation of British Troops, Battle of Britain begins, Germany starts it's Blitz on London, Race Riots in Chicago, Harlem, Los Angeles and Detroit, Popular Movies include Gone With the Wind and the Great Dictator.

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