February 23: This Day That Year
- 1660 - Charles XI became king of Sweden.
- 1855 - Carl Friedrich Gauss, German mathematician (Gaussian distribution, fundamental theorem of algebra) died (age 77).
- 1887 - French/Italian Riviera hit by Earthquake, 2,000+ people died.
- 1919 - Italy: Fascist Party formed by Benito Mussolini.
- 1944 - US forces captured Parry Island from the Japanese 1st Amphibious Brigade ending Battle of Eniwetok.
- 1945 - US Marines raised American flag on top of Mt. Suribachi, Iwo Jima. Marine Corps War Memorial sculpture derived from the photo.
- 1960 - Birthday: Naruhito, Emperor of Japan (2019-), born in Imperial Palace in Tokyo, Japan.
- 1965 - Birthday: Michael Dell computer manufacturer (Dell Technologies), born in Houston, Texas, USA.
- 1991 - US President George H. W. Bush gives Iraq a 24 hours deadline to withdraw from Kuwait or face a ground war.
- 1998 - Osama bin Laden published a fatwa declaring jihad against all Jews and Crusaders.
- 2010 - Italy: An unknown group of people pour more than 2.5 million liters of diesel oil and other hydrocarbons into the river Lambro, in Northern Italy.
- 2012 - Iraq: A series of bomb attacks across 12 Iraqi cities killed 60+ people.
- 2013 - Sudan: 50+ people were killed in conflict between rival tribes in Darfur.
- 2020 - India: Violent protests against new citizenship laws in Delhi erupted resulted in 38 deaths in next few days.