The United Kingdom left the European Union, also known as “Brexit.”
The withdrawal agreement was ratified at 23:00.
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The French government made it so that Parisian women could legally wear pants.
The first American satellite, Explorer 1, was launched into space.
A chimpanzee named Ham became the first primate to go to space aboard the US MR-2 spacecraft.
New Zealand golfer Lydia Ko became the youngest golfer to rank No. 1 in the world.
British driver Arthur MacDonald was the first to break 100 miles per hour in an automobile at Daytona Beach, Florida, US.
