April 23 is the 113th day of the year in the Gregorian Calendar (114th in leap years). There are 252 days remaining.
- 215 BC - A temple is built on the Capitoline Hill dedicated to Venus Erycina to commemorate the Roman defeat at Lake Trasum[?]
- 1014 - Battle of Clontarf: Brian Boru defeats Viking invaders, but is killed in battle
- 1348 - The Order of the Garter is founded by King Edward III of England
- 1521 - Battle of Villalar[?]: King Charles I of Spain defeats the Comuneros[?]
- 1533 The Roman Catholic Church annuls the marriage between Catherine of Aragon and Henry VIII of England
- 1597 - The Merry Wives of Windsor is first performed; Queen Elizabeth I of England was in attendance.
- 1660 - Treaty of Oliva[?] between Sweden and Poland
- 1661 - King Charles II of England, Scotland and Ireland is crowned in Westminster Abbey
- 1827 - William Rowan Hamilton presented his Theory of systems of rays
- 1867 - William Lincoln[?] patents the Zoetrope, a machine which shows animated pictures by mounting a strip of drawings in a wheel
- 1920 - The national council in Turkey denounces the government of Sultan Mehmed VI and announces a temporary constitution
- 1933 - The Gestapo is established in Germany
- 1942 - World War II: German bombers hit Exeter, Bath and York, England
- 1948 - 1948 Arab-Israeli War: Haifa, the major port of Israel, captured from Palestinian forces.
- 1954 - Hank Aaron hits his first major league home run
- 1967 - Soyuz 1 is launched into orbit, carrying a single cosmonaut, Colonel Vladimir Komarov, who is killed when the spacecraft crashes after returning to earth.
- 1968 - The United Kingdom produces its first decimalised coins, a 5p and a 10p coin.
- 1968 - Student protesters at Columbia University in New York City take over administration buildings and shut down the university
- 1990 - Namibia becomes the 160th member of the United Nations and the 50th member of the British Commonwealth
- 1993 - Eritreans vote overwhelmingly for independence from Ethiopia in a United Nations-monitored referendum
- 1994 - Physicists discover the top quark subatomic particle.
- 2001 - Intel introduces the Pentium 4 Processor.
- 2003 - Beijing closes all schools for two weeks due to the SARS virus.
- 1516 - Georg Fabricius, German poet, historian and archaeologist (+ 1571)
- 1564 - William Shakespeare, English playwright, actor - Traditional birth date. Actual date unknown (+ 1616)
- 1598 - Maarten Tromp, admiral in the Dutch navy (+ 1653)
- 1676 - King Frederick I of Sweden (+ 1751)
- 1775 - William Turner[?], painter (+ 1851)
- 1791 - James Buchanan, 15th President of the United States (+ 1868)
- 1792 - John Thomas Romney Robinson, Irish astronomer and physicist (+ 1882)
- 1813 - Stephen A. Douglas, Senator from Illinois, candidate for President of the United States (+ 1861)
- 1823 - Abd-ul-Mejid, future Ottoman sultan (+ 1861)
- 1858 - Max Planck, physicist and recipient of the Nobel Prize in physics 1918 (+ 1947)
- 1882 - Albert Coates[?], British composer (+ 1953)
- 1891 - Sergei Prokofiev, Soviet composer (+ 1953)
- 1893 - Allen Dulles, CIA director (+ 1969)
- 1893 - Frank Borzage[?], director (+ 1952)
- 1897 - Lester B. Pearson, fourteenth Prime Minister of Canada (+ 1972)
- 1899 - Vladimir Nabokov, writer (+ 1977)
- 1899 - Dame Ngaio Marsh, author (+ 1982)
- 1916 - Bud Wilkinson[?], American football coach
- 1921 - Mickey Rooney, actor
- 1921 - Warren Spahn[?], Baseball Hall of Famer
- 1923 - Avram Davidson[?], science fiction writer (+ 1993)
- 1926 - Ruth Leuwerik[?], actress
- 1928 - Shirley Temple (Shirley Temple Black), American actress and politician
- 1930 - Silvana Mangano[?], actress (+ 1989)
- 1931 - Ray Charles, American blues musician
- 1932 - Halston[?], fashion designer (+ 1990)
- 1936 - Roy Orbison, American singer and musician (+ 1988)
- 1939 - Lee Majors[?], actor
- 1941 - Paavo Lipponen, Prime Minister of Finland
- 1942 - Sandra Dee[?], actress
- 1954 - Michael Moore, filmmaker
- 1955 - Judy Davis, actress
- 1955 - Tony Miles, chess player (+ 2001)
- 1968 - Timothy McVeigh - American terrorist (+ 2001)
- 1979 - James King[?], actress
- 1014 - Brian Boru, High King of Ireland during the Battle of Clontarf (* circa 940)
- 1616 (Julian calendar) - William Shakespeare, English playwright and actor (* 1564)
- 1616 (Gregorian calendar) - Miguel Cervantes, Spanish author (* 1547)
- 1792 - Karl Friedrich Bahrdt, German theologian and adventurer (* 1741)
- 1850 - William Wordsworth, English poet (* 1770)
- 1951 - Charles G. Dawes, Vice President of the United States for Calvin Coolidge
- 1975 - William Hartnell, actor
- 1983 - Buster Crabbe, Olympics swimming gold medalist, actor
- 1986 - Otto Preminger, film director
- 1990 - Paulette Goddard[?], actress
- 1992 - Satyajit Ray, Indian filmmaker (* 1921)
- 1993 - Cesar Chavez, labor activist (* 1927)
- 1995 - Howard Cosell[?], sports journalist
- 1996 - Pamela L. Travers, author
- 1998 - James Earl Ray, assassin (* 1928)
- 2002 - Linda Lovelace, pornographic film star (* 1949)
See Also:
April 22 - April 24 - March 23 - May 23 -- listing of all days
January, February, March, April, May, June, July,
August, September, October, November, December