September 12 is the 255th day of the year (256th in leap years) in the Gregorian calendar. There are 110 days remaining until the end of the year.
1901 – 2000
- 1905 – Japanese battleship Mikasa sinks after a munitions explosion. Out of the 935 men on board, 256 are killed and 343 injured.
- 1905 – Copenhagen town hall is inaugurated in Denmark.
- 1906 – Newport Transporter Bridge is opened in Newport, south Wales.
- 1910 – First performance of Gustav Mahler's Symphony Number 8, in Munich.
- 1918 – British passenger ship Galway Castle is torpedoed by a German U-boat off Land's End, Cornwall, England, killing 143 people.
- 1920 – The 1920 Summer Olympics in Antwerp begins.
- 1928 – A hurricane in Guadeloupe kills 1,200 people.
- 1933 – Leó Szilárd has the idea of a nuclear chain reaction.
- 1940 – World-famous cave paintings are discovered in the Lascaux in southern France.
- 1940 – An explosion at the Hercules Powder Company plant in Kenil, New Jersey kills 51 and injures over 200.
- 1942 – World War II: RMS Laconia, carrying civilians, Allied soldiers, and Italian POWs, is torpedoed off the coast of West Africa, with a heavy loss of life.
- 1942 – World War II: First Day of the Battle of Edson's Ridge during the Guadalcanal Campaign. US Marines protecting Henderson Field in Guadalcanal, Solomon Islands, are attacked by Imperial Japanese forces.
- 1943 – World War II: Benito Mussolini is rescued from house arrest on the Gran Sasso in Abruzzi, led by German commandos under Otto Skorzeny.
- 1944 – World War II: American troops enter Germany near Trier.
- 1948 – Invasion of the State of Hyderabad by the Indian army on the day after the death of Pakistan's leader Muhammad Ali Jinnah.
- 1949 – Theodor Heuss becomes the 1st President of the Federal Republic of Germany.
- 1953 – John F. Kennedy marries Jacqueline Lee Bouvier in Newport, Rhode Island.
- 1958 – Jack Kilby demonstrates the first integrated circuit.
- 1959 – Showing of the first episode of Bonanza, first regularly scheduled television programme presented in colour.
- 1959 – The Soviet Union launches the Lunik II rocket.
- 1959 – Heinrich Lübke becomes the 2nd President of the Federal Republic of Germany.
- 1961 – The African and Malagasy Union is founded.
- 1964 – The Canyonlands National Park in Utah is created.
- 1966 – Gemini 11, of NASA's Gemini program, is launched.
- 1970 – Palestinian terrorists blow up three hijacked airliners in Jordan. Passengers are held at secret locations in the capital city, Amman.
- 1974 – Ethiopian Emperor Haile Selassie I is deposed in a military coup.
- 1977 – Anti-Apartheid activist Steve Biko dies in police custody.
- 1979 – Indonesia is struck by a magnitude 8.1 earthquake.
- 1980 – A military coup occurs in Turkey.
- 1988 – Hurricane Gilbert hits Jamaica.
- 1990 – The Faroe Islands national football team scores a surprise 1-0 win over the Austria national football team. The Faroese players are celebrated as heroes after their return home from the match.
- 1990 – East Germany's national football team plays its last-ever match, winning 2-0 against the Belgium national football team.
- 1992 – NASA's Space Shuttle Endeavour is launched on the STS-47 mission. On board are Mae Carol Jemison (first African American woman in space), Mamoru Mohri (first Japanese citizen on a US spaceship), and Mark Lee and Jan Davis (first married couple in space).
- 1992 – Shining Path leader Abimael Guzman is arrested in Peru, by special forces.
- 1994 – Frank Eugene Corder crashes a single-engine Cessna 150 light aircraft into the West Wing of the White House in Washington, DC, killing himself.
- 1999 – Indonesia announces it will allow international peacekeepers into East Timor.
From 2001
- 2003 – The UN lifts sanctions against Libya.
- 2003 – US Forces mistakenly shoot and kill eight Iraqi police officers in Fallujah.
- 2005 – Hong Kong Disneyland opens.
- 2007 – Former President of the Philippines Joseph Estrada is convicted of plunder.
- 2008 – The Chatsworth train collision occurs in Los Angeles, California, between a Metrolink commerce train and a Union Pacific Freight train, killing 25 people.
- 2011 – About 100 people are killed by an oil pipeline explosion in Nairobi, Kenya.
- 2011 – Russian ice hockey player Alexander Galimov dies, as the 44th, and final, victim of the Lokomotiv Yaroslavl plane crash, which occurred on September 7. The whole team was killed.
- 2015 – Jeremy Corbyn is elected leader of the British Labour Party.
- 2015 – An explosion in Petlawad in the Indian state of Madhya Pradesh kills at least 105 people.
- 2018 – The European Parliament votes by a two-thirds majority to trigger possible sanctions (punishments) against the government of Hungary, over issues of democracy, human rights, judicial freedom and journalistic freedom.
Up to 1900
- 1492 – Lorenzo II de' Medici, Duke of Urbino (d. 1519)
- 1494 – King Francis I of France (d. 1547)
- 1575 – Henry Hudson, English explorer (d. 1611)
- 1605 – William Dugdale, English antiquarian (d. 1686)
- 1649 – Giuseppe Maria Tomasi, Italian cardinal (d. 1713)
- 1652 – Frederick Charles, Duke of Württemberg-Winnental (d. 1697)
- 1688 – Ferdinand Brokoff, Czech sculptor (d. 1731)
- 1690 – Peter Dens, Belgian Catholic theologian (d. 1775)
- 1725 – Guillaume Le Gentil, French astronomer (d. 1792)
- 1736 – Hsinbyushin, King of Burma (d. 1776)
- 1740 – Johann Heinrich Jung, German writer (d. 1817)
- 1759 – Maximilian von Montgelas, Bavarian politician (d. 1838)
- 1768 – Benjamin Carr, American composer, singer, teacher and publisher (d. 1831)
- 1800 – Pierre Charles Fournier de Saint-Amant, French chess player (d. 1872)
- 1812 – Richard Hoe, American inventor and industrialist (d. 1886)
- 1818 – Richard Gatling, American weapons inventor (d. 1903)
- 1818 – Theodor Kullak, German pianist and composer (d. 1915)
- 1829 – Anselm Feuerbach, German painter (d. 1880)
- 1830 – William Sprague, 72nd Governor of Rhode Island (d. 1915)
- 1837 – Louis IV, Grand Duke of Hesse (d. 1892)
- 1838 – Arthur Auwers, German astronomer (d. 1915)
- 1852 – H. H. Asquith, Prime Minister of the United Kingdom (d. 1928)
- 1855 – William Sharp, Scottish writer (d. 1905)
- 1855 – Simon-Napoleon Parent, 12th Premier of Quebec (d. 1920)
- 1857 – Manuel Espinosa Batista, Panamanian politician and businessman (d. 1919)
- 1857 – George Hendrik Breitner, Dutch painter (d. 1923)
- 1865 – Sophus Claussen, Danish writer (d. 1931)
- 1866 – Freeman Freeman-Thompson, 1st Marquess of Willingdon, 13th Governor General of Canada (d. 1941)
- 1875 – Matsunosuke Onoe, Japanese actor (d. 1926)
- 1880 – H. L. Mencken, American journalist and writer (d. 1956)
- 1885 – Heinrich Hoffmann, German photographer (d. 1957)
- 1887 – Yusif Vazir Chamanzaminli, Azerbaijani writer and statesman (d. 1943)
- 1888 – Maurice Chevalier, French singer and actor (d. 1972)
- 1889 – Ugo Pasquale Mifsud, 3rd Prime Minister of Malta (d. 1942)
- 1891 – Don Pedro Albizu Campos, advocate for Puerto Rican independence (d. 1965)
- 1891 – Fred Kelly, American athlete (d. 1974)
- 1891 – Arthur Hays Sulzberger, American publisher (d. 1968)
- 1892 – Alfred A. Knopf, American publisher (d. 1984)
- 1894 – Friedrich Ebert, Jr., German politician (d. 1979)
- 1894 – Billy Gilbert, American actor and composer (d. 1971)
- 1897 – Irène Joliot-Curie, French physicist, recipient of the Nobel Prize in Chemistry (d. 1956)
- 1898 – Salvador Bacarisse, Spanish composer (d. 1963)
1901 – 1950
- 1901 – Ben Blue, Canadian actor and comedian (d. 1975)
- 1901 – Shmuel Horowitz, Russian-Israeli agronomist (d. 1999)
- 1902 – Juscelino Kubitschek de Oliveira, President of Brazil (d. 1976)
- 1904 – Gavriil Popov, Russian composer (d. 1972)
- 1904 – Istvan Horthy, Hungarian admiral (d. 1942)
- 1907 – Roger Bonvin, Swiss Federal Councillor (d. 1982)
- 1912 – Frances Lennon, English artist (d. 2015)
- 1913 – Jesse Owens, American athlete, four-time Olympic champion (d. 1980)
- 1913 – Eiji Toyoda, Japanese industrialist (d. 2013)
- 1914 – Desmond Llewelyn, Welsh actor (d. 1999)
- 1915 – Frank McGee, American journalist (d. 1974)
- 1916 – Tony Bettenhausen, American race car driver (d. 1961)
- 1921 – Stanislaw Lem, Polish writer (d. 2006)
- 1922 – Antonio Cafiero, Argentine politician (d. 2014)
- 1924 – Amilcar Cabral, Cape Verdean-Guinea-Bissauan politician (d. 1973)
- 1925 – Stan Lopata, American baseball player (d. 2013)
- 1925 – Dickie Moore, American actor (d. 2015)
- 1927 – Mathé Altéry, French soprano and actress
- 1928 – Ernie Vandeweghe, American basketball player (d. 2014)
- 1930 – Gunder Gundersen, Norwegian skier (d. 2005)
- 1930 – Akira Suzuki, Japanese chemist
- 1931 – Sir Ian Holm, English actor
- 1931 – George Jones, American singer (d. 2013)
- 1931 – Adrian Rogers, American religious leader (d. 2005)
- 1932 – Atli Dam, 5th Prime Minister of the Faroe Islands (d. 2005)
- 1933 – Tatiana Doronina, Russian actress
- 1934 – Jaegwon Kim, Korean-American philosopher
- 1934 – Glenn Davis, American athlete (d. 2009)
- 1937 – George Chuvalo, Canadian boxer
- 1938 – Claude Ruel, French-Canadian ice hockey coach (d. 2015)
- 1939 – Nobuyuki Oishi, Japanese footballer
- 1939 – Henry Waxman, United States Congressman
- 1940 – Joachim Frank, German-American biophysicist, joint 2017 Nobel Prize in Chemistry winner
- 1940 – Mickey Lolich, American baseball player
- 1940 – Linda Gray, American actress
- 1943 – Maria Muldaur, American singer
- 1943 – Michael Ondaatje, Sri Lankan-born writer
- 1944 – Leonard Peltier, Native American activist
- 1944 – Yoshio Kikugawa, Japanese footballer
- 1944 – Barry White, American singer (d. 2003)
- 1944 – Vladimir Spivakov, Russian violinist and conductor
- 1944 – Colin Young, American singer
- 1949 – Irina Rodnina, Russian figure skater
- 1949 – Charles Burlingame, American pilot (d. 2001)
1951 – 1975
- 1951 – Joe Pantoliano, American actor
- 1951 – Bertie Ahern, Irish politician and former Taoiseach
- 1951 – Ali-Ollie Woodson, American singer and musician (d. 2010)
- 1952 – Neil Peart, Canadian musician and writer (Rush) (d. 2020)
- 1952 – Gerry Beckley, American musician
- 1953 – Fiona Mactaggart, Scottish politician
- 1954 – Peter Scolari, American actor
- 1956 – Leslie Cheung, Hong Kong singer (d. 2003)
- 1956 – Ricky Rudd, American race car driver
- 1956 – Sam Brownback, American politician, 46th Governor of Kansas
- 1956 – Brian Robertson, Scottish singer-songwriter and guitarist
- 1957 – Hans Zimmer, German composer
- 1957 – Rachel Ward, English actress
- 1958 – Wilfredo Benitez, American boxer
- 1959 – Sigmar Gabriel, German politician
- 1959 – Scott Brown, United States Senator
- 1959 – Hisashi Kaneko, Japanese footballer
- 1960 – Stefanos Korkolis, Greek songwriter and pianist
- 1961 – Mylène Farmer, French singer-songwriter
- 1962 – Amy Yasbeck, American actress
- 1964 – Dieter Hecking, German footballer
- 1966 – Ben Folds, American musician
- 1966 – Vezio Sacratini, Italian ice hockey player
- 1967 – Mirko Slomka, German footballer and manager
- 1967 – Pat Listach, American baseball player
- 1968 – Paul F. Tompkins, American comedian, actor and screenwriter
- 1969 – Mika Myllyla, Finnish cross-country skier (d. 2011)
- 1969 – Angel Cabrera, Argentine golfer
- 1969 – Shigeki Maruyama, Japanese golfer
- 1971 – Chandra Sturrup, Bahamanian athlete
- 1973 – Darren Campbell, British athlete
- 1973 – Martin Lapointe, Canadian ice hockey player
- 1973 – Paul Walker, American actor (d. 2013)
- 1974 – Caroline Aigle, French pilot (d. 2007)
- 1974 – Nuno Valente, Portuguese footballer
From 1976
- 1976 – Maciej Zurawski, Polish footballer
- 1976 – 2 Chainz, American rapper
- 1976 – Lauren Stamile, American actress
- 1977 – Nathan Bracken, Australian cricketer
- 1977 – James McCartney, British musician
- 1978 – Ruben Studdard, American singer
- 1980 – Sean Burroughs, American baseball player
- 1980 – Josef Vasicek, Czech ice hockey player (d. 2011)
- 1980 – Yao Ming, Chinese basketball player
- 1981 – Jennifer Hudson, American singer and actress
- 1983 – Sergio Parisse, Argentine-born Italian rugby player
- 1984 – September, Swedish singer
- 1985 – Hiroki Mizumoto, Japanese footballer
- 1986 – Yuto Nagatomo, Japanese footballer
- 1986 – Joanne Jackson, British swimmer
- 1986 – Emmy Rossum, American actress and singer
- 1987 – Yaroslava Shvedova, Kazakhstani tennis player
- 1988 – Amanda Jenssen, Swedish singer-songwriter and guitarist
- 1989 – Freddie Freeman, American baseball player
- 1992 – Sviatlana Pirazhenka, Belarussian tennis player
- 1993 – Kelsea Ballerini, American singer
- 1994 – Elina Svitolina, Ukrainian tennis player
- 1994 – Mhairi Black, Scottish politician
- 1996 – Colin Ford, American actor
Up to 1900
- 640 – Sak K'uk', Maya Queen of Palenque
- 1185 – Andronikos I Komnenos, Byzantine Emperor (b. 1118)
- 1213 – Peter II of Aragon (b. 1174)
- 1348 – Joan the Lame, Queen of France (b. 1293)
- 1362 – Pope Innocent VI (b. 1295)
- 1369 – Blanche of Lancaster (b. 1345)
- 1500 – Albert III, Duke of Saxony (b. 1443)
- 1612 – Tsar Vasili IV of Russia (b. 1552)
- 1660 – Jacob Cats, Dutch poet, jurist and politician (b. 1577)
- 1683 – King Afonso VI of Portugal (b. 1643)
- 1691 – John George III, Elector of Saxony (b. 1647)
- 1764 – Jean-Philippe Rameau, French composer (b. 1683)
- 1829 – Juan Ignacio Molina, Chilean naturalist (b. 1740)
- 1870 – Fitz Hugh Ludlow, American writer (b. 1836)
- 1874 – François Guizot, 22nd Prime Minister of France (b. 1787)
- 1885 – Ranbir Singh, 2nd Maharaja of Jammu and Kashmir (b. 1830)
1901 – 2000
- 1903 – Duncan Gillies, Australian politician, 14th Premier of Victoria (b. 1834)
- 1907 – Ilia Chavchavadze, Georgian poet, journalist and lawyer (b. 1837)
- 1918 – George Reid, 4th Prime Minister of Australia (b. 1845)
- 1919 – Leonid Andreyev, Russian writer (b. 1871)
- 1929 – Rainis, Latvian poet, playwright and politician (b. 1865)
- 1938 – Prince Arthur of Connaught (b. 1883)
- 1945 – Hajime Sugiyama, Japanese general (b. 1880)
- 1956 – Hans Carossa, German writer (b. 1878)
- 1956 – Sandor Festetics, Hungarian politician (b. 1882)
- 1960 – Dino Borgioli, Italian tenor (b. 1891)
- 1977 – Steve Biko, South African anti-Apartheid activist (b. 1946)
- 1977 – Robert Lowell, American poet (b. 1917)
- 1981 – Eugenio Montale, Italian poet (b. 1896)
- 1982 – Federico Moreno Torroba, Spanish composer (b. 1891)
- 1986 – Jacques Henri Lartigue, French photographer (b. 1894)
- 1992 – Anthony Perkins, American actor (b. 1932)
- 1993 – Raymond Burr, Canadian actor (b. 1917)
- 1994 – Boris Yegorov, Russian physician and cosmonaut (b. 1937)
- 1995 – Jeremy Brett, English actor (b. 1933)
- 1995 – Yasutomo Nagai, Japanese motorcycle racer (b. 1965)
- 1996 – Ernesto Geisel, President of Brazil (b. 1907)
- 2000 – Gary Olsen, English actor (b. 1957)
From 2001
- 2001 – Victor Wong, Chinese-American actor (b. 1927)
- 2003 – Johnny Cash, American country music singer (b. 1932)
- 2004 – Max Abramowitz, American architect (b. 1908)
- 2008 – David Foster Wallace, American writer (b. 1962)
- 2009 – Norman Borlaug, American agronomist (b. 1914)
- 2009 – Jack Kramer, American tennis player (b. 1921)
- 2009 – Willy Ronis, French photographer (b. 1910)
- 2010 – Claude Chabrol, French movie director (b. 1930)
- 2011 – Alexander Galimov, Russian ice hockey player (b. 1985)
- 2012 – Sid Watkins, British neurosurgeon (b. 1928)
- 2012 – Derek Jameson, British tabloid journalist and broadcaster (b. 1929)
- 2013 – Erich Loest, German writer (b. 1926)
- 2013 – Otto Sander, German actor (b. 1941)
- 2013 – Ray Dolby, American engineer and inventor (b. 1933)
- 2014 – Atef Ebeid, Prime Minister of Egypt (b. 1932)
- 2014 – Ian Paisley, Northern Irish religious and political leader (b. 1926)
- 2014 – John Bardon, English actor (b. 1939)
- 2014 – Joe Sample, American pianist and composer (b. 1939)
- 2014 – Antony Kidman, Australian psychologist, biochemist and writer (b. 1938)
- 2015 – Adrian Frutiger, Swiss typeface designer (b. 1928)
- 2016 – Gunilla Bernadotte, Swedish duchess (b. 1923)
- 2016 – Ellen Burka, Canadian-Dutch figure skater (b. 1921)
- 2016 – Stanley Steinbaum, American activist (b. 1920)
- 2017 – Heiner Geissler, German politician (b. 1930)
- 2017 – Alex Hawkins, American football player (b. 1937)
- 2017 – Siegfried Köhler, German conductor (b. 1923)
- 2017 – Allan MacEachen, Canadian politician (b. 1921)
- 2017 – Edith Windsor, American LGBT rights activist and technological manager at IBM (b. 1929)
- 2018 – Henry Kalis, American politician (b. 1937)
- 2018 – Hans Kloss, German artist and graphic designer (b. 1938)
- 2018 – Walter Mischel, Austrian-American psychologist (b. 1930)
- 2018 – Billy O'Dell, American baseball player (b. 1933)
- 2018 – Shen Chun-shan, Taiwanese physicist and academic (b. 1932)
- 2018 – Rachid Taha, Algerian singer, songwriter and activist (b. 1958)