| 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.
