What are the important events that happened on September 23? Here are historical events, facts, and some myths about this day.

September 23: Facts & Myths About This Day

September 23 is the 266^th day of the year 2025 in the Gregorian calendar. There are 99 days remaining until the end of this year. The day of the week is Tuesday.

Under the Julian calendar, this day is September 10, 2025 – a Tuesday. Both day of the week are the same but did you notice the difference with the Gregorian calendar?

When this day started, 29,309,760 minutes has elapsed since midnight of January 1, 1970 – the Unix epoch.

Strange as it may, if we name this day after a polygon then it will be called ‘dihectahexacontahexagon’ day.

Virgo is the zodiac sign of a person born on this day. Sapphire is the modern birthstone for this month. Agate is the mystical birthstone from Tibetan origin that dates back over a thousand years.

According to the lunisolar Chinese calendar, there are 147 days remaining before the start of the next Chinese New Year.

The ancient Maya civilization believes that the end of the world will happen on December 21, 2012. There are now 4,659 days since this fabled cataclysmic event.

September 23: This Day In History

It is frequently the day of the Autumnal Equinox in the Northern Hemisphere and the day of the Vernal Equinox in the Southern Hemisphere.

September 23 Historical Events

• 1122 –
  Pope Calixtus II and Holy Roman Emperor Henry V agree to the Concordat of Worms to put an end to the Investiture Controversy.
• 1409 –
  Battle of Kherlen, the second significant victory over Ming China by the Mongols since 1368.
• 1641 –
  The Merchant Royal, carrying a treasure worth over a billion US dollars, is lost at sea off Land’s End.
• 1905 –
  Norway and Sweden sign the “Karlstad treaty”, peacefully dissolving the Union between the two countries.
• 1938 –
  Mobilization of the Czechoslovak army in response to the Munich Crisis.
• 1959 –
  Iowa farmer and corn breeder Roswell Garst hosts Soviet premier Nikita Khrushchev.
• 1969 –
  The Chicago Eight trial opens in Chicago.
• 1983 –
  Gulf Air Flight 771 is bombed, killing all 117 people on board.
• 1988 –
  José Canseco of the Oakland Athletics becomes the first member of the 40-40 club.
• 1999 –
  Qantas Flight 1 overruns the runway in Bangkok during a storm. Although some passengers only receive minor injuries, it is still the worst crash in Qantas’s history since 1960.

Who were born on September 23?

• 1907 –
  Dominique Aury, French novelist (d. 1998)
• 1936 –
  Dr. Tareq Suheimat, Jordanian physician, nephrologist
• 1943 –
  Marty Schottenheimer, American football coach
• 1972 –
  Ana Marie Cox, American blogger and author
• 1973 –
  Ingrid Fliter, Argentinian pianist
• 1975 –
  Jaime Bergman, American model and actress
• 1976 –
  Wladimir Sidorenko, Ukrainian boxer
• 1978 –
  Keri Lynn Pratt, American actress
• 1981 –
  Misti Traya, American actress
• 1985 –
  Joba Chamberlain, American baseball player

Who died on September 23?

• 1390 –
  John I, Duke of Lorraine (b. 1346)
• 1571 –
  John Jewel, English bishop (b. 1522)
• 1675 –
  Valentin Conrart, founder of the Académie Française (b. 1603)
• 1830 –
  Elizabeth Kortright Monroe, American First Lady (b. 1768)
• 1844 –
  Alexander von Benckendorff, Russian general and statesman (b. 1783)
• 1900 –
  William Marsh Rice, American philanthropist and university founder (b. 1816)
• 1974 –
  Robbie McIntosh, Scottish musician (Average White Band) (b. 1950)
• 1992 –
  James Van Fleet, U.S. Army general (b. 1892)
• 1998 –
  Mary Frann, American actress (b. 1943)
• 2006 –
  Sir Malcolm Arnold, English composer and professional trumpeter (b. 1921)