History of the Day for:
April 23
- 1564: The birth of William Shakespeare, England's greatest playwright, is traditionally celebrated. He died on the same date in 1616.
- 1616: Spanish novelist and playwright Miguel de Cervantes Saavedra ("Don Quixote") died in Madrid.
- 1789: President?elect George Washington and his wife moved into the Franklin House in New York, the first executive mansion.
- 1791: The 15th president of the United States, James Buchanan, was born in Franklin County, Pa.
- 1850: William Wordsworth, British poet, died aged 80.
- 1858: German theoretical physicist Max Planck, who developed the quantum theory, was born.
- 1896: The "Vitascope" system for projecting movies onto a screen was demonstrated in New York City.
- 1941: World War II: The Greek government and King George II evacuate Athens before the invading Wehrmacht.
- 1942: World War II: Baedeker Blitz – German bombers hit Exeter, Bath and York in retaliation for the British raid on Lübeck.
- 1945: The Russian army liberated the Sachsenhausen and Ravensbrueck concentration camps.
- 1954: Hank Aaron hit the first of his record 755 major-league home runs, in a game between the Milwaukee Braves and the St. Louis Cardinals.
- 1968: The Methodist Church and the Evangelical United Brethren Church merged, forming the United Methodist Church.
- 1969: Sirhan Sirhan was sentenced to death for the assassination of Sen. Robert F. Kennedy.
- 1985: Coca-Cola announced it was changing the secret flavor formula for Coke.
- 1988: A federal smoking ban during domestic airline flights of two hours or less went into effect.
- 1993: Labor leader Cesar Chavez died in San Luis, Ariz., at age 66.
- 1997: Omaria massacre in Algeria: 42 villagers are killed.
- 2003: Beijing closes all schools for two weeks because of the SARS virus.
- 2009: The gamma ray burst GRB 090423 it's observed for 10 seconds as the most distant object of any kind and also the oldest known object in the universe.