Wikipedia:Selected anniversaries/December 21
- 69 - Vespasian (pictured) became the fourth Roman Emperor in the Year of the Four Emperors.
- 1913 - Arthur Wynne published the first crossword puzzle in the New York World.
- 1937 - The animated feature film Snow White and the Seven Dwarfs, based on the fairy tale Snow White by the Brothers Grimm, premiered to a widely receptive audience.
- 1962 - Rondane National Park, Norway's first national park, was established.
- 1988 - Pan Am Flight 103: A terrorist bomb exploded and destroyed a Boeing 747 over Lockerbie, Scotland, killing 270, including 11 on the ground.
Recent days: December 20 – December 19 – December 18
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