It would still be a year before the United States joined, but in 1940, World War II was in full swing for everyone else.
Germany occupied France, London was a city under arial siege, and the rest of the world wasn't far behind.
From soldiers in the heat of battle, to children going about their innocent daily lives, here are 24 photos showing what life was like in 1940.
3
Famous friends in 1940.
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Showing off to his daughter, Australia, 1940.
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The children of hop-pickers take cover in a trench in Kent, whilst watching a dogfight overhead during the Battle of Britain.
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Claiborne County, Tennessee, 1940.
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He was chosen as an example of the ideal male body by the University of Southern California's fine arts department.
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At the beach, Zandvoort, August of 1940.
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A cafe in Paris on Bastille Day, July, 1940.
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Performing a stop and search, 1940.
14
Wearing a rebellious mini-skirt.
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As seen from up high, 1940.
17
Entering a Soldatenbordell, which is a former synagog.
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14 years old in 1940. Buckingham Palace.
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In Hollywood Park, 1940.
22
Leaving her recently bombed home to get married, London, 1940.
23
Atlantic City, at the segregated Chicken Bone Beach. 1940.
24
A staged photo, but cool nonetheless. 1940.