September 23 is the 266th day of the year (267th in leap years) in the Gregorian calendar; 99 days remain until the end of the year.
1901–present 1905 – Norway and Sweden sign the Karlstad Treaty, peacefully dissolving the Union between the two countries.
1913 – The United Mine Workers of America launch a strike which eventually escalated into the Colorado Coalfield War.[13] 1918 – World War I: British forces capture Haifa, Acre, and Es Salt from the Ottoman Empire.[14][15] 1920 – The Louisiana hurricane dissipates over Kansas[16] after forcing around 4,500 people to evacuate[17] and causing $1.45 million in damages.[16] 1932 – Saudi National Day: Crown Prince (later king) Faisal of Saudi Arabia, on behalf of Ibn Saud, proclaims the unification of the Kingdom of Saudi Arabia, the current iteration of the Third Saudi State.[18] 1942 – World War II: The Matanikau action on Guadalcanal begins: U.S. Marines attack Japanese units along the Matanikau River.
1947 – A magnitude 6.9 earthquake strikes South Khorasan in Iran, killing over 500 people.[19] 1950 – Korean War: The Battle of Hill 282 is the first US friendly-fire incident on British military personnel since World War II.
1951 – George VI, king of the United Kingdom, has his left lung removed in an operation after a malignant tumour was found.[20] 1952 – After being accused of financial improprieties, Senator Richard Nixon delivers his 'Checkers speech' nationwide on television and radio, defending his actions and successfully salvaging his nomination as the Republican candidate for Vice President.[21] 1955 – An all-white jury in Mississippi finds Roy Bryant and J. W. Milam not guilty in the torture-murder of 14year-old African American boy Emmett Till.[22] 1956 – A tropical storm originating in the eastern Pacific Ocean passes into the Gulf of Mexico and is upgraded and named Hurricane Flossy just hours before striking the Gulf Coast and causing 15 deaths and an estimated US$24.8 million in damages.[ 23] 1957 – Little Rock schools integration crisis: President Dwight D. Eisenhower sends the 101st Airborne Division to Little Rock, Arkansas, and federalizes the Arkansas National Guard, ordering both to support the integration of Little Rock Central High School.[24] 1961 – U.S. President John F. Kennedy nominates African American civil rights lawyer Thurgood Marshall to the Court of Appeals for the Second Circuit,[25] although pro-segregation Southern senators manage to delay his confirmation until September 11, 1962.[26] 1962 – Flying Tiger Line Flight 923, a Lockheed L-1049H Super Constellation registered as N6923C, ditches into the Atlantic Ocean killing 28 out the 76 occupants onboard. The remaining 48 were rescued six hours later.[27][28] 1964 – Typhoon Wilda, one of the strongest typhoons to ever strike Japan, makes landfall,[29] causing at least 30 fatalities[ 30] and sinking at least 64 ships.[31] 1967 – Seven people die, 46 people are injured, and more than 150 boats capsize when a squall hits Lake Michigan during Michigan's first coho salmon sport fishing season.[32] 1973 – Argentine general election: Juan Perón returns to power in Argentina.