|Holiday name||Holiday location||Holiday type|
|Saudi National Day||Saudi Arabia||National Holiday|
|Checkers Day||-||Unofficial (Animals, Weird & Obscure)|
|Celebrate Bisexuality Day||-||Unofficial (Lifestyle, Relationships & Family)|
|National Great American Pot Pie Day||-||Unofficial (Food & Drinks)|
|National Snack Stick Day||-||Unofficial (Food & Drinks)|
|National Teal Talk Day||-||Unofficial (Awareness & Cause, Health & Body)|
|National Singles Day||-||Unofficial (Lifestyle)|
|National Seat Check Saturday||-||Unofficial (Awareness & Cause, Health & Body)|
|National Hunting and Fishing Day||-||Unofficial (Activity & Action, Sports)|
|September Equinox||Multiple [Show]||Season|
|September equinox||Multiple [Show]||Season|
|Martyrdom of Imam Hasan al-Askari||Iran||National Holiday|
|Autumn Equinox||Japan||National Holiday|
|Mabon||-||(Culture & History)|
Historical Events on September 23
- 1642: The first commencement exercises begin for Harvard College.
- 1779: The USS Bonhomme Richard wins the Battle of Flamborough Head during the American Revolutionary War.
- 1780: During the American Revolutionary War, American soldiers arrest British Major John Andre as a spy; This situation ends up exposing Benedict Arnold’s switching of sides.
- 1806: After exploring the Pacific Northwest of the U.S., Lewis and Clark return to the city of St. Louis in Missouri.
- 1887: The fourth oldest university in India – the University of Allahabad – is founded on this day.
- 1908: On this day, the University of Alberta is started.
- 1942: United States Marines attack Japanese forces along the Matanikau river during World War II.
- 1943: The Italian Social Republic is founded during World War II.
- 1962: The Lincoln Center for the Performing Arts opens its doors in New York City.
- 1980: Bob Marley plays his last concert in the city of Pittsburgh, Pennsylvania.
- 1983: Saint Kitts and Nevis joins the U.N.
- 1983: A bomb explodes on Gulf Air Flight 771, destroying it and killing all 117 people who were aboard.
- 1999: It’s announced by NASA that contact with the Mars Climate Orbiter has been lost.
- 2004: After Hurrican Jeanne causes mass flooding and mudslides in Haiti, over three thousand people are killed.
- 2008: Ten people are killed by Matti Saari during the Kauhajoki school shooting before he kills himself.
Famous Birthdays on September 23
- Greek playwright Euripides is born in 480 BC.
- Roman emperor Augustus is born in 63 BC.
- Japanese Emperor Takakura is born in 1161.
- Mongolian Emperor Kublai Khan is born in 1215.
- American saxophonist and composer John Coltrane is born in 1926.
- Pakistani poet and songwriter Sehba Akhtar is born in 1930.
- Northern Irish Actor Colin Blakely is born in 1930.
- American singer-songwriter and pianist Ray Charles is born in 1930.
- Swiss ice hockey player Yannick Weber is born in 1988.
- American basketball player Brandon Jennings is born in 1989.