May 21

Events 
 Up to 1900 
 293 – Roman Emperors Diocletian and Maximian appoint Galerius as Caesar to Diocletian.
 878 – Syracuse, Italy is captured by the Muslim Sultan of Sicily.
 879 – Pope John VIII gives blessings to Branimir of Croatia and to the Croatian people.
 996 – Otto III, Holy Roman Emperor is crowned.
 1085 – The city of Helsingborg is founded in what is now southern Sweden.
 1471 – Henry VI of England, the last King from the House of Lancaster, is murdered in the Tower of London on the orders of King Edward IV of England.
 1502 – The island of Saint Helena is discovered by Portuguese explorer Joao da Nova.
 1674 – The nobility elect John Sobieski to become King of Poland and Grand Duke of Lithuania.
 1792 – The Unzen volcano in Japan erupts, resulting in thousands of people getting killed.
 1809 – Napoleonic Wars: First day of the Battle of Aspern-Essling – Austria, under Archduke Charles, Duke of Teschen and France, under Napoleon Bonaparte, meet in battle, with Napoleon's side winning the next day.
 1851 – Colombia abolishes slavery.
 1856 – The town of Lawrence, Kansas, is captured and burned by pro–Slavery forces.
 1863 – American Civil War: The Union Army closes off the last escape route  from Port Hudson, Louisiana, in preparation for the coming siege.
 1863 – Organization of the Seventh-day Adventist Church in Battle Creek, Michigan, United States.
 1864 – American Civil War: The Battle of Spotsylvania Court House ends.
 1871 – French troops invade the Paris Commune and engage its residents in street fighting.
 1879 – War of the Pacific: The naval Battle of Iquique takes place between Chile and Peru.
 1881 – The American Red Cross is founded by Clara Barton.
 1894 – The Manchester Ship Canal is opened in England by Queen Victoria.

 1901 – 2000 
 1904 – FIFA, the world governing body of football, is founded in Paris.
 1911 – President of Mexico Porfirio Díaz and revolutionary Francisco I. Madero sign the Treaty of Ciudad Juarez.
 1917 – A significant part of Atlanta, Georgia, United States, is destroyed by fire.
 1924 – University of Chicago students Richard Loeb and Nathan Leopold murder 14–year–old Bobby Franks in a "thrill killing".
 1925 – In Tokyo, Japan, scientist Hidesaburo Ueno dies. His dog, Hachiko, keeps waiting for him, and becomes well known for his loyalty.
 1927 – Charles Lindbergh flies across the Atlantic Ocean.
 1932 – Amelia Earhart is forced by bad weather to land near Derry, Northern Ireland, after becoming the first woman to fly solo across the Atlantic Ocean.
 1934 – Oskaloosa, Iowa becomes the first municipality in the United States to fingerprint all of its citizens.
 1939 – Canada's National War Memorial is unveiled by King George VI of the United Kingdom and Elizabeth Bowes-Lyon.
 1946 – Physicist Louis Slotin is fatally irradiated in a criticality incident during an experiment with a demon core at the Los Alamos National Laboratory in New Mexico, United States.
 1965 – The current Flag of Ontario is adopted.
 1966 – The Ulster Volunteer Force declares war on the IRA.
 1976 – The Yuba City bus disaster in Martinez, California kills 29 people.
 1990 – The Democratic Republic of Yemen and North Yemen agree to merge to become the Republic of Yemen.
 1991 – Ethiopian President Mengistu Haile Mariam flees Ethiopia.
 1991 – Indian Prime Minister Rajiv Gandhi is murdered in Sriperumbudur in southern India.
 1994 – The Democratic Republic of Yemen tries to secede, leading to the break–out of war.
 1996 – The ship MV Bukoba sinks in Tanzanian waters on Lake Victoria, killing around 1,000 people.
 1998 – President of Indonesia Suharto announces his resignation.

 From 2001 
 2003 – An earthquake in northern Algeria kills more than 2,000 people.
 2005 – Elena Paparizou wins the 50th Eurovision Song Contest for Greece, in Kyiv, Ukraine.
 2006 – The majority of voters in Montenegro vote to split from Serbia and Montenegro. Montenegro becomes independent on June 3.
 2007 – The clipper Cutty Sark is damaged by fire in London, UK.
 2011 – American pastor Harold Camping predicted the end of the world to begin on this date, with the rapture, supposedly leading to the end itself on October 21. Despite his prediction, life continued as normal.
 2012 – A bombing in Sana'a, Yemen kills 120 people.
 2013 – Far–right French historian Dominique Venner commits suicide by gunshot in Notre Dame Cathedral, Paris.
 2022 – 2022 Australian federal election is held.

 Births 
 Up to 1900 
 427 BC – Plato, Influential Greek philosopher (d. 347 BC)
 120 BC – Aurelia Cotta, mother of Julius Caesar (d. 54 BC)
 1471 – Albrecht Dürer, German painter and graphic artist (d. 1528)
 1527 – King Philip II of Spain (d. 1598)
 1653 – Eleonora Maria Josefa of Austria (d. 1697)
 1688 – Alexander Pope, English poet (d. 1744)
 1759 – Joseph Fouché, French politician (d. 1820)
 1780 – Elizabeth Fry, British social reformer and philanthropist (d. 1845)
 1785 – August Immanuel Bekker, German classical philologist (d. 1871)
 1792 – Gaspard-Gustave Coriolis, French scientist (d. 1843)
 1799 – Mary Anning, English paleontologist (d. 1847)
 1827 – William P. Sprague, American politician (d. 1899)
 1837 – Itagaki Taisuke, Japanese politician (d. 1919)
 1843 – Charles Albert Gobat, Swiss politician (d. 1914)
 1843 – Louis Renault, French jurist (d. 1918)
 1844 – Henri Rousseau, French artist (d. 1910)
 1850 – Giuseppe Mercalli, Italian volcanologist (d. 1914)
 1851 – Léon Bourgeois, French statesman (d. 1925)
 1853 – Edward Gawlor Prior, Canadian politician, 12th Premier of British Columbia (d. 1920)
 1855 – Emile Verhaeren, Belgian poet (d. 1916)
 1856 – Jose Batlle y Ordonez, Uruguayan politician (d. 1929)
 1857 – Francisco Aguilar Barquero, President of Costa Rica (d. 1924)
 1860 – Willem Einthoven, Dutch doctor, won the 1924 Nobel Prize in Physiology or Medicine, inventor of the electrocardiogram (d. 1927)
 1863 – Archduke Eugen of Austria (d. 1954)
 1864 – Princess Stephanie of Belgium (d. 1945)
 1873 – Hans Berger, German neuroscientist (d. 1941)
 1878 – Glenn Curtiss, American aviation pioneer (d. 1930)
 1880 – Tudor Arghezi, Romanian poet and writer (d. 1967)
 1884 – Manuel Pérez y Curis, Uruguayan poet (d. 1920) 
 1898 – Armand Hammer, physician, entrepreneur, oil magnate, and art collector (d. 1990)

 1901 – 1950 
 1901 – Horace Heidt, band leader (d. 1986)
 1901 – Sam Jaffe, American producer (d. 2000)
 1902 – Earl Averill, American Baseball Hall of Famer (d. 1983)
 1902 – Marcel Lajos Breuer, architect (d. 1981)
 1903 – Manly Wade Wellman, writer (d. 1986)
 1904 – Fats Waller, African-American pianist (d. 1943)
 1904 – Robert Montgomery, American actor (d. 1981)
 1907 – John C. Allen, American roller coaster designer (d. 1979)
 1912 – Monty Stratton, American Major League Baseball pitcher (d. 1982)
 1916 – Harold Robbins, American novelist (d. 1997)
 1916 – Tinus Osendarp, Dutch sprinter (d. 2002)
 1917 – Raymond Burr, American actor (d. 1993)
 1920 – John Chadwick, British classical philologist (d. 1998)
 1921 – Andrei Sakharov, Russian physicist and human rights activist, recipient of the Nobel Prize (d. 1989)
 1922 – Pio Laghi, Italian cardinal (d. 2009)
 1923 – Armand Borel, Swiss mathematician (d. 2003)
 1923 – Ara Parseghian, American football coach (d. 2017)
 1923 – Vernon Biever, American photographer (d. 2010)
 1924 – Atanas Semerdzhiev, Vice President of Bulgaria (d. 2015)
 1924 – Peggy Cass, American actress, comedienne, game show panellist and announcer (d. 1999)
 1930 – Gil Bartosh, American football player and coach (d. 2016)
 1930 – Malcolm Fraser, 22nd Prime Minister of Australia (d. 2015)
 1932 – Inese Jaunzeme, Latvian javelin thrower (d. 2011)
 1932 – Jean Stablinski, French cyclist (d. 2007)
 1932 – Gabriele Wohmann, German writer (d. 2015)
 1933 – Maurice André, French trumpet player (d. 2012)
 1934 – Bengt I. Samuelsson, Swedish biochemist
 1934 – Jack Twyman, American basketball player (d. 2012)
 1935 – Terry Lightfoot, English clarinettist and bandleader
 1936 – Günter Blobel, German biologist (d. 2018)
 1938 – Urs Widmer, Swiss writer (d. 2014)
 1939 – Heinz Holliger, Swiss musician, composer and conductor
 1940 – Tony Sheridan, English musician (d. 2013)
 1941 – Martin Carthy, English singer and guitarist
 1941 – Ronald Isley, American singer-songwriter, producer and actor
 1942 – David Hunt, Baron Hunt of Wirral, English politician
 1943 – Hilton Valentine, English musician
 1944 – Mary Robinson, former President of Ireland
 1945 – Ernst Messerschmid, German physicist and astronaut
 1948 – Leo Sayer, English musician
 1948 – Denis MacShane, Scottish politician
 1949 – Andrew Neil, Scottish broadcasting executive

 1951 – 1975 
 1951 – Al Franken, American comedian and former United States Senator
 1951 – Adrian Hardiman, Irish judge (d. 2016)
 1952 – Mr. T (Laurence Tureaud), American actor
 1954 – Janice Karman, American voice actress
 1954 – Kathleen Wynne, Canadian politician, 25th Premier of Ontario
 1956 – Judge Reinhold, American actor
 1957 – Nadine Dorries, British politician
 1957 – Tony Hayward, British businessman
 1957 – Renée Soutendijk, Dutch actress
 1959 – Abdulla Yameen, 6th President of the Maldives
 1959 – Loretta Lynch, 83rd United States Attorney General
 1959 – Nick Cassavetes, American actor and director
 1960 – Jeffrey Dahmer, American serial killer (d. 1994)
 1963 – Kevin Shields, American–Irish singer–songwriter
 1964 – Nancy Benoit, American professional wrestler (d. 2007)
 1964 – Drew Hendry, Scottish politician
 1966 – Andrzej Lesiak, Polish footballer
 1967 – Chris Benoit, American professional wrestler (d. 2007)
 1967 – Lisa Edelstein, American actress
 1968 – Tom Goodman-Hill, English actor
 1968 – Julie Vega, Filipino actress and singer (d. 1985)
 1969 – Georgiy Gongadze, Georgian–Ukrainian journalist (d. 2000)
 1969 – Pierluigi Brivio, Italian footballer
 1972 – The Notorious B.I.G., American musician (d. 1997)
 1972 – Adriano Cintra, Brazilian singer, guitarist and producer
 1973 – Noel Fielding, English comedian, actor and screenwriter
 1973 – Stewart Cink, American golfer
 1975 – Lee Gaze, Welsh guitarist (Lostprophets)
 1975 – Juuso Pykalisto, Finnish rally driver

 From 1976 
 1976 – Stuart Bingham, English snooker player
 1976 – Aditi Govitrikar, Indian model, actress and physician
 1977 – Quinton Fortune, South African footballer
 1978 – Briana Banks, American actress
 1979 – Jamie Hepburn, Scottish footballer
 1980 – Gotye, Belgian–born Australian singer and musician
 1980 – Chris Raab, American actor and stuntman
 1980 – Anna Rogowska, Polish athlete
 1981 – Edson Buddle, American soccer player
 1981 – Max, German singer
 1985 – Mutya Buena, English singer (Sugababes)
 1985 – Mark Cavendish, Manx cyclist
 1985 – Alexander Dale Oen, Norwegian swimmer (d. 2012)
 1985 – Marco Carta, Italian singer
 1986 – Mario Mandzukic, Croatian footballer
 1987 – Ashlie Brillault, actress
 1987 – Masato Morishige, Japanese footballer
 1988 – Claire Cashmore, British paralympic swimmer
 1988 – Park Gyu-ri, South Korean singer and actress
 1989 – Emily Robins, New Zealand actress and singer
 1989 – Hal Robson-Kanu, Welsh footballer
 1991 – Sarah Ramos, American actress
 1992 – Olivia Olson, American actress and singer-songwriter
 1992 – Hutch Dano, American actor
 1994 – Tom Daley, British diver

 Deaths 
 Up to 1950 
 987 – King Louis V of France (b. 967)
 1237 – Olaf the Black, King of Mann and the Isles
 1254 – Conrad IV of Germany (b. 1228)
 1471 – King Henry VI of England (b. 1421)
 1481 – King Christian I of Denmark, Norway and Sweden (b. 1426)
 1512 – Pandolfo Petrucci, Italian ruler (b. 1452)
 1542 – Hernando de Soto, Spanish explorer and conquistador (b. c. 1496)
 1639 – Tommaso Campanella, Italian theologian (b. 1568)
 1670 – Niccolo Zucchi, Italian astronomer and physicist (b. 1586) 
 1686 – Otto von Guericke, German scientist (b. 1602)
 1719 – Pierre Poiret, French mystic and philosopher (b. 1646)
 1844 – Giuseppe Baini, Italian composer (b. 1775)
 1879 – Arturo Prat, Chilean naval officer (b. 1848)
 1891 – Alphonso Taft, American politician (b. 1810)
 1895 – Franz von Suppe, Austrian composer (b. 1819)
 1911 – Williamina Fleming, Scottish astronomer (b. 1857)
 1915 – Leonid Gobyato, Russian general (b. 1875)
 1915 – Knud Knudsen, Norwegian photographer (b. 1832)
 1919 – Yevgraf Fyodorov, Russian mathematician (b. 1853)
 1920 – Venustiano Carranza, President of Mexico (b. 1859)
 1924 – Bobby Franks, American teenager, murdered in "thrill killing" (b. 1910)
 1925 – Hidesaburo Ueno, Japanese scientist (b. 1872)
 1929 – Archibald Primrose, 5th Earl of Rosebery, Prime Minister of the United Kingdom (b. 1847)
 1935 – Jane Addams, American social reformer (b. 1860)
 1946 – Louis Slotin, physicist
 1949 – Klaus Mann, German writer (b. 1906)

 1951 – 2000 
 1952 – John Garfield, American actor (b. 1913)
 1957 – Alexander Vertinsky, Russian actor, singer, composer and poet (b. 1889)
 1964 – James Franck, German–born physicist (b. 1882)
 1965 – Geoffrey de Havilland, British aircraft designer (b. 1882)
 1973 – Carlo Emilio Gadda, Italian writer and poet (b. 1893)
 1973 – Vaughn Monroe, American singer, trumpeter, bandleader and actor (b. 1911)
 1988 – Sammy Davis, Sr., American dancer (b. 1900)
 1991 – Rajiv Gandhi, Prime Minister of India (b. 1944)
 1994 – Giovanni Goria, Prime Minister of Italy (b. 1943)
 1994 – Ralph Miliband, Belgian–born sociologist and father of David and Ed Miliband (b. 1924)
 1995 – Les Aspin, 18th United States Secretary of Defense (b. 1938)
 1998 – Robert Gist, American actor and director (b. 1917)
 2000 – Dame Barbara Cartland, English writer (b. 1901)
 2000 – John Gielgud, English actor (b. 1904)
 2000 – Erich Mielke, East German politician (b. 1907)

 From 2001 
 2002 – Niki de Saint Phalle, French painter (b. 1930)
 2003 – Alejandro de Tomaso, Argentine racing driver (b. 1928)
 2003 – Frank D. White, Governor of Arkansas (b. 1933)
 2006 – Katherine Dunham, American dancer, director, educator and writer (b. 1909)
 2011 – Bill Hunter, Australian actor (b. 1940)
 2013 – Trevor Bolder, English rock musician, songwriter and record producer (b. 1950)
 2013 – Mohammad Khaled Hossain, Bangladeshi mountaineer (b. 1979)
 2013 – Dominique Venner, French historian and writer (b. 1935)
 2014 – Jaime Lusinchi, former President of Venezuela (b. 1924)
 2014 – Poni Adams, American actress (b. 1918)
 2014 – Alireza Soleimani, Iranian wrestler (b. 1956)
 2015 – Annarita Sidoti, Italian race walker (b. 1970)
 2015 – Twinkle, British singer-songwriter (b. 1948)
 2015 – Louis Johnson, American musician (b. 1955)
 2016 – Gaston Berghmans, Belgian comedian and actor (b. 1926)
 2016 – Sándor Tarics, Hungarian water polo player (b. 1913)
 2016 – Akhtar Mansour, Afghan Islamist (b. 1968)
 2016 – Nick Menza, American drummer (Megadeth) (b. 1964)
 2017 – Kenny Cordray, American guitarist and songwriter (b. 1954)
 2017 – Paul Judge, British businessman and political executive (b. 1949)
 2017 – Jimmy LaFave, American folk musician and singer–songwriter (b. 1955)
 2017 – Bill White, Canadian ice hockey player (b. 1939)
 2018 – Anna Maria Ferrero, Italian actress (b. 1934)
 2018 – Dovey Johnson Roundtree, American civil rights activist and attorney (b. 1914)
 2018 – Pedro Tenorio, Governor of the Northern Marianas (b. 1934)
 2018 – Clint Walker, American actor (b. 1927)
 2018 – Faith Whittlesey, American politician and diplomat (b. 1939)
 2018 – António Arnault, Portuguese poet and politician (b. 1936)
 2018 – Gholamreza Hassani, Iranian Islamic leader (b. 1928)
 2018 – Allyn Ann McLerie, Canadian–American actress (b. 1926)
 2019 – Glauco Sansovini, former Captain–Regent of San Marino (b. 1938)
 2019 – Binyavanga Wainaina, Kenyan writer (b. 1971)
 2019 – Ali Mohammad Mahar, Pakistani politician (b. 1967)

 Observances 
 Navy Day (Chile)
 Afro-Colombian Day (Colombia)
 Independence Day (Montenegro)
 Saint Helena Day
 Day of Patriots and the Military (Hungary)

Category:Days of the year