September 21: International Day of Peace and Peace One Day; Independence Day in Malta (1964), Belize (1981) & Armenia (1991).
- 1792 - French Revolution: The National Convention voted to abolish the monarchy, and the First Republic was proclaimed.
- 1823 - According to Joseph Smith, Jr., the angel Moroni appeared to him and revealed the location of the hidden Golden Plates, which contained the ancient sacred texts of the Book of Mormon.
- 1898 - The Hundred Days' Reform in China was abruptly terminated when Empress Dowager Cixi (pictured) forced the reform-minded Guangxu Emperor into seclusion and took over the government as regent.
- 1937 - J. R. R. Tolkien's The Hobbit, a predecessor to The Lord of the Rings, was first published.
- 1942 - The prototype model of the B-29 Superfortress flew for the first time.
Recent days: September 20 – September 19 – September 18
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