May 20 is the 140th day of the year (141st in leap years) in the Gregorian calendar; 225 days remain until the end of the year.

• 325 – The First Council of Nicaea is formally opened, starting the first ecumenical council of the Christian Church.^[1]
• 491 – Empress Ariadne marries Anastasius I. The widowed Augusta is able to choose her successor for the Byzantine throne, after Zeno (late emperor) dies of dysentery.
• 685 – The Battle of Dun Nechtain is fought between a Pictish army under King Bridei III and the invading Northumbrians under King Ecgfrith, who are decisively defeated.
• 794 – While visiting the royal Mercian court at Sutton Walls with a view to marrying princess Ælfthryth, King Æthelberht II of East Anglia is taken captive and beheaded.^[2]
• 1217 – The Second Battle of Lincoln is fought near Lincoln, England, resulting in the defeat of Prince Louis of France by William Marshal, 1st Earl of Pembroke.
• 1293 – King Sancho IV of Castile creates the Estudio de Escuelas de Generales in Alcalá de Henares.
• 1426 – King Mohnyin Thado formally ascends to the throne of Ava.^{[note 1]}
• 1449 – The Battle of Alfarrobeira is fought, establishing the House of Braganza as a principal royal family of Portugal.
• 1497 – John Cabot sets sail from Bristol, England, on his ship Matthew looking for a route to the west (other documents give a May 2 date).
• 1498 – Portuguese explorer Vasco da Gama discovers the sea route to India when he arrives at Kozhikode (previously known as Calicut), India.^[3]
• 1520 – Hernan Cortés defeats Pánfilo de Narváez, sent by Spain to punish him for insubordination.^[4]
• 1521 – Ignatius of Loyola is seriously wounded in the Battle of Pampeluna.
• 1570 – Cartographer Abraham Ortelius issues Theatrum Orbis Terrarum, the first modern atlas.

• 1609 – Shakespeare's sonnets are first published in London, perhaps illicitly, by the publisher Thomas Thorpe.^[5]
• 1631 – The city of Magdeburg in Germany is seized by forces of the Holy Roman Empire and most of its inhabitants massacred, in one of the bloodiest incidents of the Thirty Years' War.
• 1645 – Yangzhou massacre: The ten day massacre of 800,000 residents of the city of Yangzhou, part of the Transition from Ming to Qing.^[6]
• 1714 – Johann Sebastian Bach leads the first performance of his cantata for Pentecost, Erschallet, ihr Lieder, BWV 172, at the chapel of Schloss Weimar.^[7]
• 1741 – The Battle of Cartagena de Indias ends in a Spanish victory and the British begin withdrawal towards Jamaica with substantial losses.
• 1775 – The Mecklenburg Declaration of Independence is allegedly signed in Charlotte, North Carolina.
• 1802 – By the Law of 20 May 1802, Napoleon Bonaparte reinstates slavery in the French colonies, revoking its abolition in the French Revolution.
• 1813 – Napoleon Bonaparte leads his French troops into the Battle of Bautzen in Saxony, Germany, against the combined armies of Russia and Prussia. The battle ends the next day with a French victory.
• 1861 – American Civil War: The state of Kentucky proclaims its neutrality, which will last until September 3 when Confederate forces enter the state. Meanwhile, the State of North Carolina secedes from the Union.
• 1862 – U.S. President Abraham Lincoln signs the Homestead Act into law, opening eighty-four million acres (340,000 km²) of public land to settlers.^[8]
• 1864 – American Civil War: Battle of Ware Bottom Church: In the Virginia Bermuda Hundred campaign, 10,000 troops fight in this Confederate victory.
• 1873 – Levi Strauss and Jacob Davis receive a U.S. patent for blue jeans with copper rivets.^[9]
• 1875 – Signing of the Metre Convention by 17 nations leading to the establishment of the International System of Units.
• 1882 – The Triple Alliance between the German Empire, Austria-Hungary and the Kingdom of Italy is formed.
• 1883 – Krakatoa begins to erupt; the volcano explodes three months later, killing more than 36,000 people.
• 1891 – History of cinema: The first public display of Thomas Edison's prototype kinetoscope.

• 1902 – Cuba gains independence from the United States. Tomás Estrada Palma becomes the country's first President.
• 1927 – Treaty of Jeddah: The United Kingdom recognizes the sovereignty of King Ibn Saud in the Kingdoms of Hejaz and Nejd, which later merge to become the Kingdom of Saudi Arabia.
• 1927 – Charles Lindbergh takes off for Paris from Roosevelt Field in Long Island, N.Y., aboard the Spirit of St. Louis on the first nonstop solo flight across the Atlantic Ocean, landing 33+1⁄2 hours later.^[10]
• 1932 – Amelia Earhart takes off from Newfoundland to begin the world's first solo nonstop flight across the Atlantic Ocean by a female pilot, landing in Ireland the next day.
• 1940 – The Holocaust: The first prisoners arrive at a new concentration camp at Auschwitz.
• 1941 – World War II: Battle of Crete: German paratroops invade Crete.
• 1943 – The Luttra Woman, a bog body from the Early Neolithic period (radiocarbon-dated c. 3928–3651 BC),^[11] was discovered near Luttra, Sweden.^[12]
• 1948 – Generalissimo Chiang Kai-shek wins the 1948 Republic of China presidential election and is sworn in as the first President of the Republic of China at Nanjing.
• 1949 – In the United States, the Armed Forces Security Agency, the predecessor to the National Security Agency, is established.
• 1956 – In Operation Redwing, the first United States airborne hydrogen bomb is dropped over Bikini Atoll in the Pacific Ocean.
• 1958 – Capital Airlines Flight 300 collides in mid-air with a United States Air Force Lockheed T-33 over Brunswick, Maryland, killing 12.^[13]
• 1964 – Discovery of the cosmic microwave background radiation by Robert Woodrow Wilson and Arno Penzias.
• 1965 – One hundred twenty-one people are killed when Pakistan International Airlines Flight 705 crashes at Cairo International Airport.^[14]
• 1967 – The Popular Movement of the Revolution political party is established in the Democratic Republic of the Congo.
• 1969 – The Battle of Hamburger Hill in Vietnam ends.
• 1971 – In the Chuknagar massacre, Pakistani forces massacre thousands, mostly Bengali Hindus.
• 1980 – In a referendum in Quebec, the population rejects, with 60% of the vote, a government proposal to move towards independence from Canada.
• 1983 – First publications of the discovery of the HIV virus that causes AIDS in the journal Science by a team of French scientists including Françoise Barré-Sinoussi, Jean-Claude Chermann, and Luc Montagnier.^[15]
• 1983 – Church Street bombing: A car bomb planted by UMkhonto we Sizwe explodes on Church Street in South Africa's capital, Pretoria, killing 19 people and injuring 217 others.
• 1985 – Radio Martí, part of the Voice of America service, begins broadcasting to Cuba.
• 1989 – The Chinese authorities declare martial law in the face of pro-democracy demonstrations, setting the scene for the Tiananmen Square massacre.
• 1990 – The first post-Communist presidential and parliamentary elections are held in Romania.
• 1996 – Civil rights: The Supreme Court of the United States rules in Romer v. Evans against a law that would have prevented any city, town or county in the state of Colorado from taking any legislative, executive, or judicial action to protect the rights of gays and lesbians.^[16]
• 2002 – The independence of East Timor is recognized by Portugal, formally ending 23 years of Indonesian rule and three years of provisional UN administration (Portugal itself is the former colonizer of East Timor until 1976).
• 2009 – An Indonesian Air Force Lockheed L-100 Hercules crashes in Magetan Regency, killing 99.^[17]
• 2011 – Mamata Banerjee is sworn in as the Chief Minister of West Bengal, the first woman to hold this post.^[18]
• 2012 – At least 27 people are killed and 50 others injured when a 6.0-magnitude earthquake strikes northern Italy.
• 2013 – An EF5 tornado strikes the Oklahoma City suburb of Moore, killing 24 people and injuring 377 others.
• 2016 – The government of Singapore authorised the controversial execution of convicted murderer Kho Jabing for the murder of a Chinese construction worker despite the international pleas for clemency, notably from Amnesty International and the United Nations.^[19][20][21]
• 2019 – The International System of Units (SI): The base units are redefined, making the international prototype of the kilogram obsolete.
• 2022 – Russo-Ukrainian War: Russia claims full control of the Ukrainian city of Mariupol after a nearly three-month siege.^[22]

• 1315 – Bonne of Luxembourg, first wife of John II of France (d. 1349)
• 1470 – Pietro Bembo, Italian cardinal, poet, and scholar (d. 1547)
• 1505 – Levinus Lemnius, Dutch writer (d. 1568)
• 1531 – Thado Minsaw of Ava, Viceroy of Ava (d. 1584)
• 1537 – Hieronymus Fabricius, Italian anatomist (d. 1619)
• 1575 – Robert Heath, English judge and politician (d. 1649)

• 1664 – Andreas Schlüter, German sculptor and architect (d. 1714)
• 1726 – Francis Cotes, English painter and academic (d. 1770)
• 1759 – William Thornton, Virgin Islander-American architect, designed the United States Capitol (d. 1828)
• 1769 – Andreas Vokos Miaoulis, Greek admiral and politician (d. 1835)
• 1772 – Sir William Congreve, 2nd Baronet, English inventor and politician, developed Congreve rockets (d. 1828)
• 1776 – Simon Fraser, American-Canadian fur trader and explorer (d. 1862)
• 1795 – Pedro María de Anaya, Mexican soldier. President (1847–1848) (d. 1854)^[23]
• 1799 – Honoré de Balzac, French novelist and playwright (d. 1850)
• 1806 – John Stuart Mill, English economist, civil servant, and philosopher (d. 1873)
• 1811 – Alfred Domett, English-New Zealand poet and politician, 4th Prime Minister of New Zealand (d. 1887)
• 1818 – William Fargo, American businessman and politician, co-founded Wells Fargo and American Express (d. 1881)
• 1822 – Frédéric Passy, French economist and academic, Nobel Prize laureate (d. 1912)
• 1824 – Cadmus M. Wilcox, Confederate States Army general (d. 1890)
• 1825 – Antoinette Brown Blackwell, the first woman to be ordained as a mainstream Protestant minister in the U.S. (d. 1921)
• 1830 – Hector Malot, French author (d. 1907)
• 1838 – Jules Méline, French lawyer and politician, 65th Prime Minister of France (d. 1925)
• 1851 – Emile Berliner, German-American inventor, invented the Gramophone record (d. 1929)
• 1854 – George Prendergast, Australian politician, 28th Premier of Victoria (d. 1937)
• 1856 – Henri-Edmond Cross, French Neo-Impressionist painter (d. 1910)
• 1860 – Eduard Buchner, German chemist, zymologist, and academic, Nobel Prize laureate (d. 1917)
• 1875 – Hendrik Offerhaus, Dutch rower (d. 1953)
• 1877 – Pat Leahy, Irish-American jumper (d. 1927)
• 1879 – Hans Meerwein, German chemist (d. 1965)
• 1882 – Sigrid Undset, Danish-Norwegian novelist, essayist, and translator, Nobel Prize laureate (d. 1949)
• 1883 – Faisal I of Iraq (d. 1933)
• 1886 – Ali Sami Yen, Turkish footballer and manager, founded the Galatasaray Sports Club (d. 1951)
• 1894 – Chandrashekarendra Saraswati, Indian guru and scholar (d. 1994)
• 1895 – R. J. Mitchell, English engineer, designed the Supermarine Spitfire and Supermarine S.6B (d. 1937)
• 1897 – Diego Abad de Santillán, Spanish economist and author (d. 1983)
• 1897 – Malcolm Nokes, English hammer and discus thrower (d. 1986)
• 1898 – Eduard Ole, Estonian painter (d. 1995)
• 1899 – Aleksandr Deyneka, Russian painter and sculptor (d. 1969)
• 1899 – John Marshall Harlan II, American lawyer and jurist (d. 1971)
• 1900 – Sumitranandan Pant, Indian poet and author (d. 1977)

• 1901 – Max Euwe, Dutch chess player, mathematician, and author (d. 1981)
• 1901 – Doris Fleeson, American journalist (d. 1970)
• 1904 – Margery Allingham, English author of detective fiction (d. 1966)
• 1906 – Giuseppe Siri, Italian cardinal (d. 1989)
• 1907 – Carl Mydans, American photographer and journalist (d. 2004)
• 1908 – Henry Bolte, Australian politician, 38th Premier of Victoria (d. 1990)
• 1908 – Louis Daquin, French actor and director (d. 1980)
• 1908 – Francis Raymond Fosberg, American botanist and author (d. 1993)
• 1908 – James Stewart, American actor (d. 1997)
• 1911 – Gardner Fox, American author (d. 1986)
• 1911 – Annie M. G. Schmidt, Dutch author and playwright (d. 1995)
• 1913 – Teodoro Fernández, Peruvian footballer (d. 1996)
• 1913 – William Redington Hewlett, American engineer, co-founded Hewlett-Packard (d. 2001)
• 1913 – Carlos J. Gradin, Argentine Archaeologist (d. 2002)^[24][25]
• 1915 – Peter Copley, English actor (d. 2008)
• 1915 – Moshe Dayan, Israeli general and politician, 5th Israeli Minister of Foreign Affairs (d. 1981)
• 1915 – Joff Ellen, Australian comedian and actor (d. 1999)
• 1916 – Owen Chadwick, English rugby player, historian, and academic (d. 2015)
• 1916 – Alexey Maresyev, Russian soldier and pilot (d. 2001)
• 1916 – Ondina Valla, Italian sprinter and hurdler (d. 2006)
• 1917 – Tony Cliff, Israeli-English author and activist (d. 2000)
• 1917 – Guy Favreau, Canadian lawyer, judge, and politician, 28th Canadian Minister of Justice (d. 1967)
• 1918 – Alexandra Boyko, Russian tank commander (d. 1996)
• 1918 – Edward B. Lewis, American biologist, geneticist, and academic, Nobel Prize laureate (d. 2004)
• 1919 – George Gobel, American comedian (d. 1991)
• 1920 – John Cruickshank, Scottish lieutenant and banker, Victoria Cross recipient
• 1921 – Wolfgang Borchert, German author and playwright (d. 1947)
• 1921 – Hal Newhouser, American baseball player and scout (d. 1998)
• 1921 – Hao Wang, Chinese-American logician, philosopher, and mathematician (d. 1995)
• 1922 – Ted Hinton, Northern Irish international footballer (d. 1988)^[26]
• 1923 – Edith Fellows, American actress (d. 2011)
• 1923 – Sam Selvon, Trinidad-born writer (d. 1994)^[27]
• 1924 – David Chavchavadze, English-American CIA officer and author (d. 2014)
• 1924 – Zelmar Michelini, Uruguayan journalist and politician (d. 1976)
• 1925 – Alexei Tupolev, Russian engineer, designed the Tupolev Tu-144 (d. 2001)
• 1926 – Bob Sweikert, American race car driver (d. 1956)
• 1927 – Bud Grant, American football player and coach (d. 2023)
• 1927 – David Hedison, American actor (d. 2019)
• 1927 – Franciszek Macharski, Polish cardinal (d. 2016)
• 1929 – Pedro Trebbau, German-born Venezuelan zoologist (d. 2021)^[28]
• 1929 – Gilles Loiselle, Canadian politician and diplomat, 33rd Canadian Minister of Finance (d. 2022)
• 1930 – Sam Etcheverry, American football player and coach (d. 2009)
• 1931 – Ken Boyer, American baseball player and manager (d. 1982)
• 1931 – Louis Smith, American trumpeter (d. 2016)
• 1933 – Constance Towers, American actress and singer
• 1935 – José Mujica, Uruguayan guerrilla leader and politician, 40th President of Uruguay
• 1936 – Anthony Zerbe, American actor
• 1937 – Dave Hill, American golfer (d. 2011)
• 1937 – Derek Lampe, English footballer^[29]
• 1939 – Balu Mahendra, Sri Lankan-Indian director, cinematographer, and screenwriter (d. 2014)
• 1940 – Shorty Long, American singer-songwriter and producer (d. 1969)
• 1940 – Stan Mikita, Slovak-Canadian ice hockey player and sportscaster (d. 2018)
• 1940 – Sadaharu Oh, Japanese-Taiwanese baseball player and manager
• 1941 – Goh Chok Tong, Singaporean politician, 2nd Prime Minister of Singapore
• 1941 – John Strasberg, American actor and teacher
• 1942 – Raymond Chrétien, Canadian lawyer and diplomat, Canadian Ambassador to the United States
• 1942 – Lynn Davies, Welsh sprinter and long jumper
• 1942 – Carlos Hathcock, American sergeant and sniper (d. 1999)
• 1942 – Frew McMillan, South African tennis player
• 1943 – Albano Carrisi, Italian singer, actor, and winemaker
• 1943 – Deryck Murray, Trinidadian cricketer
• 1944 – Joe Cocker, English singer-songwriter (d. 2014)
• 1944 – Boudewijn de Groot, Indonesian-Dutch singer-songwriter and guitarist
• 1944 – Keith Fletcher, English cricketer and manager
• 1944 – Dietrich Mateschitz, Austrian businessman, co-founder of Red Bull GmbH (d. 2022)^[30]
• 1945 – Vladimiro Montesinos, Peruvian intelligence officer
• 1946 – Cher, American singer-songwriter, producer, and actress
• 1946 – Bobby Murcer, American baseball player, coach, manager, and sportscaster (d. 2008)
• 1947 – Steve Currie, English bass player (d. 1981)
• 1947 – Greg Dyke, English journalist and academic
• 1949 – Robert Morin, Canadian director, cinematographer, and screenwriter
• 1949 – Michèle Roberts, English author and poet
• 1949 – Dave Thomas, Canadian actor, director, producer, and screenwriter
• 1950 – Andy Johns, English-American engineer and producer (d. 2013)
• 1950 – Reinaldo Merlo, Argentinian footballer and coach
• 1950 – Jane Parker-Smith, English organist (d. 2020)^[31]
• 1951 – Thomas Akers, American colonel, engineer, and astronaut
• 1951 – Christie Blatchford, Canadian newspaper columnist, journalist and broadcaster (d. 2020)^[32]
• 1951 – Mike Crapo, American lawyer and politician
• 1952 – Roger Milla, Cameroonian footballer and manager
• 1952 – Michael Wills, English politician, British Minister of Justice
• 1953 – Robert Doyle, Australian educator and politician, 103rd Lord Mayor of Melbourne
• 1954 – David Paterson, American lawyer and politician, 55th Governor of New York
• 1954 – Colin Sutherland, Lord Carloway, Scottish lawyer and judge
• 1955 – Steve George, American keyboard player and songwriter
• 1955 – Zbigniew Preisner, Polish composer and producer
• 1956 – Ingvar Ambjørnsen, Norwegian-German author and critic
• 1956 – Gerry Peyton, English born Irish international footballer and coach^[33]
• 1956 – Douglas Preston, American journalist and author
• 1957 – Yoshihiko Noda, Japanese lawyer and politician, 62nd Prime Minister of Japan
• 1958 – Ron Reagan, American journalist and radio host
• 1958 – Jane Wiedlin, American singer-songwriter, guitarist, and actress
• 1959 – Susan Cowsill, American singer-songwriter
• 1960 – Tony Goldwyn, American actor and director
• 1961 – Clive Allen, English international footballer and manager^[34]
• 1961 – Nick Heyward, English singer-songwriter and guitarist
• 1963 – David Wells, American baseball player and sportscaster
• 1964 – Kōichirō Genba, Japanese politician, 80th Japanese Minister for Foreign Affairs
• 1964 – Edin Osmanović, Slovenian footballer, coach, and manager
• 1964 – Charles Spencer, 9th Earl Spencer, English journalist and author
• 1965 – Ted Allen, American television host and author
• 1965 – Stu Grimson, Canadian ice hockey player, sportscaster, and lawyer
• 1966 – Dan Abrams, American journalist and author
• 1967 – Graham Brady, English politician
• 1967 – Gabriele Muccino, Italian director, producer, and screenwriter
• 1968 – Timothy Olyphant, American actor and producer
• 1969 – Road Dogg, American wrestler, producer, and soldier
• 1970 – Terrell Brandon, American basketball player
• 1970 – Louis Theroux, Singaporean-English journalist and producer
• 1971 – Šárka Kašpárková, Czech triple jumper and coach
• 1971 – Tony Stewart, American race car driver
• 1972 – Michael Diamond, Australian shooter
• 1972 – Christophe Dominici, French rugby player (d. 2020)
• 1972 – Busta Rhymes, American rapper, producer, and actor
• 1973 – Nathan Long, Australian rugby league player
• 1974 – Allison Amend, American novelist and short story writer
• 1974 – Shiboprosad Mukherjee, Indian film director, writer and actor
• 1975 – Juan Minujín, Argentinian actor, director, and screenwriter
• 1976 – Ramón Hernández, Venezuelan-American baseball player
• 1976 – Tomoya Satozaki, Japanese baseball player
• 1977 – Matt Czuchry, American actor
• 1977 – Leo Franco, Argentinian footballer
• 1977 – Angela Goethals, American actress
• 1977 – Stirling Mortlock, Australian rugby player
• 1977 – Vesa Toskala, Finnish ice hockey player
• 1978 – Hristos Banikas, Greek chess player
• 1978 – Pavla Hamáčková-Rybová, Czech pole vaulter
• 1978 – Nils Schumann, German runner
• 1979 – Andrew Scheer, Canadian politician, 28th Leader of the Conservative Party of Canada
• 1979 – Jayson Werth, American baseball player
• 1980 – Austin Kearns, American baseball player
• 1980 – Kassim Osgood, American football player
• 1981 – Iker Casillas, Spanish footballer
• 1981 – Rachel Platten, American singer and songwriter
• 1981 – Lindsay Taylor, American basketball player
• 1981 – Mark Winterbottom, Australian race car driver
• 1982 – Petr Čech, Czech footballer
• 1982 – Imran Farhat, Pakistani cricketer
• 1982 – Jessica Raine, English actress
• 1982 – Daniel Ribeiro, Brazilian director, producer, and screenwriter
• 1983 – Óscar Cardozo, Paraguayan footballer
• 1983 – Matt Langridge, English rower
• 1984 – Mauro Rafael da Silva, Brazilian footballer
• 1984 – Patrick Ewing Jr., American basketball player
• 1984 – Keith Grennan, American football player
• 1985 – Chris Froome, Kenyan-English cyclist
• 1985 – Brendon Goddard, Australian footballer^[35]
• 1986 – Dexter Blackstock, English footballer^[36]
• 1986 – Stéphane Mbia, Cameroonian footballer
• 1986 – Jiřina Svobodová, Czech pole vaulter
• 1987 – Mike Havenaar, Japanese footballer
• 1987 – Julian Wright, American basketball player
• 1988 – Joel Moon, Australian rugby league player^[37]
• 1989 – Siosia Vave, Australian-Tongan rugby league player
• 1991 – Bastian Baker, Swiss singer, songwriter, and performer
• 1991 – Emre Çolak, Turkish footballer
• 1992 – Cate Campbell, Malawian-Australian swimmer
• 1992 – Jack Gleeson, Irish actor
• 1992 – Enes Kanter, Turkish basketball player
• 1992 – Fanny Smith, Swiss freestyle skier^[38]
• 1993 – Ramy Rabia, Egyptian footballer^[39]
• 1993 – Caroline Zhang, American figure skater^[40]
• 1996 – Brian Kelly, Australian rugby league player
• 1998 – Jamie Chadwick, English race car driver
• 1998 – Nam Nguyen, Canadian figure skater

• 685 – Ecgfrith of Northumbria (b. 645)
• 794 – Æthelberht II, king of East Anglia
• 965 – Gero the Great, Saxon ruler (b.c. 900)
• 1062 – Bao Zheng, Chinese magistrate and mayor of Kaifeng (b. 999)
• 1277 – Pope John XXI (b. 1215)
• 1285 – John I of Cyprus (b. 1259)
• 1291 – Sufi Saint Sayyid Jalaluddin Surkh-Posh Bukhari
• 1366 – Maria of Calabria, Empress of Constantinople (b. 1329)
• 1444 – Bernardino of Siena, Italian-Spanish missionary and saint (b. 1380)
• 1449 – Álvaro Vaz de Almada, 1st Count of Avranches
• 1449 – Infante Pedro, Duke of Coimbra (b. 1392)
• 1501 – Columba of Rieti, Italian Dominican tertiary Religious Sister (b. 1467)
• 1503 – Lorenzo di Pierfrancesco de' Medici, Italian banker and politician (b. 1463)
• 1506 – Christopher Columbus, Italian explorer, early European explorer of the Americas (b. 1451)^[41]
• 1550 – Ashikaga Yoshiharu, Japanese shōgun (b. 1510)
• 1579 – Isabella Markham, English courtier (b. 1527)

• 1622 – Osman II, Ottoman sultan (b. 1604)
• 1645 – Shi Kefa, Chinese general and calligrapher (b. 1601)
• 1648 – Władysław IV Vasa, Polish son of Sigismund III Vasa (b. 1595)
• 1677 – George Digby, 2nd Earl of Bristol, Spanish-English politician, English Secretary of State (b. 1612)
• 1713 – Thomas Sprat, English bishop (b. 1635)
• 1717 – John Trevor, Welsh lawyer and politician, 102nd Speaker of the House of Commons (b. 1637)
• 1722 – Sébastien Vaillant, French botanist and mycologist (b. 1669)
• 1732 – Thomas Boston, Scottish author and educator (b. 1676)
• 1782 – William Emerson, English mathematician and academic (b. 1701)
• 1793 – Charles Bonnet, Swiss botanist and biologist (b. 1720)
• 1812 – Count Hieronymus von Colloredo, Austrian archbishop (b. 1732)
• 1834 – Gilbert du Motier, Marquis de Lafayette, French general (b. 1757)
• 1841 – Joseph Blanco White, Spanish poet and theologian (b. 1775)
• 1864 – John Clare, English poet (b. 1793)
• 1873 – George-Étienne Cartier, Canadian soldier, lawyer, and politician, 9th Premier of East Canada (b. 1814)
• 1880 – Ana Néri, Brazilian nurse and philanthropist (b. 1814)^[42]
• 1896 – Clara Schumann, German pianist and composer (b. 1819)

• 1909 – Ernest Hogan, American actor and composer (b. 1859)
• 1917 – Valentine Fleming, Scottish soldier and politician (b. 1887)
• 1917 – Philipp von Ferrary, Italian stamp collector (b. 1850)
• 1924 – Bogd Khan, Mongolian ruler (c. 1869)
• 1925 – Joseph Howard, Maltese politician, 1st Prime Minister of Malta (b. 1862)
• 1931 – Ernest Noel, Scottish businessman and politician (b. 1831)
• 1940 – Verner von Heidenstam, Swedish author and poet, Nobel Prize laureate (b. 1859)
• 1942 – Hector Guimard, French Architect (b. 1867)
• 1946 – Jacob Ellehammer, Danish pilot and engineer (b. 1871)
• 1947 – Philipp Lenard, Slovak-German physicist and academic, Nobel Prize laureate (b. 1862)
• 1947 – Georgios Siantos, Greek sergeant and politician (b. 1890)
• 1949 – Damaskinos of Athens, Greek archbishop and politician, 137th Prime Minister of Greece (b. 1891)
• 1956 – Max Beerbohm, English essayist, parodist, and caricaturist (b. 1872)
• 1956 – Zoltán Halmay, Hungarian swimmer and trainer (b. 1881)
• 1961 – Josef Priller, German colonel and pilot (b. 1915)
• 1962 – Timothy (Szretter), a Polish Orthodox clergyman, the third Metropolitan of Warsaw and all Poland (b. 1901)^[43]
• 1964 – Rudy Lewis, American singer (b. 1936)
• 1971 – Waldo Williams, Welsh poet and academic (b. 1904)
• 1973 – Renzo Pasolini, Italian motorcycle racer (b. 1938)
• 1973 – Jarno Saarinen, Finnish motorcycle racer (b. 1945)
• 1975 – Barbara Hepworth, English sculptor and lithographer (b. 1903)
• 1976 – Syd Howe, Canadian ice hockey player (b. 1911)
• 1976 – Zelmar Michelini, Uruguayan journalist and politician (b. 1924)
• 1976 – Héctor Gutiérrez Ruiz, Uruguayan politician (b. 1934)
• 1989 – John Hicks, English economist and academic, Nobel Prize laureate (b. 1904)
• 1989 – Gilda Radner, American actress and comedian (b. 1946)
• 1995 – Les Cowie, Australian rugby league player (b. 1925)
• 1996 – Jon Pertwee, English actor, portrayed the Third Doctor (b. 1919)
• 1998 – Robert Normann, Norwegian guitarist (b. 1916)
• 2000 – Jean-Pierre Rampal, French flute player (b. 1922)
• 2000 – Malik Sealy, American basketball player and actor (b. 1970)
• 2000 – Yevgeny Khrunov, Russian colonel, engineer, and astronaut (b. 1933)
• 2001 – Renato Carosone, Italian singer-songwriter and pianist (b. 1920)
• 2002 – Stephen Jay Gould, American paleontologist, biologist, and academic (b. 1941)
• 2005 – Paul Ricœur, French philosopher and academic (b. 1913)
• 2005 – William Seawell, American general (b. 1918)
• 2007 – Norman Von Nida, Australian golfer (b. 1914)
• 2008 – Hamilton Jordan, American politician, 8th White House Chief of Staff (b. 1944)
• 2009 – Arthur Erickson, Canadian architect and urban planner, designed Roy Thomson Hall (b. 1924)
• 2009 – Lucy Gordon, American actress and model (b. 1980)^[44]
• 2009 – Pierre Gamarra, French author, poet, and critic (b. 1919)
• 2011 – Randy Savage, American wrestler and actor (b. 1952)
• 2012 – Leela Dube, Indian anthropologist and scholar (b. 1923)
• 2012 – Robin Gibb, Manx-English singer-songwriter and producer (b. 1949)
• 2012 – David Littman, English-Swiss historian, author, and academic (b. 1933)
• 2012 – Ken Lyons, American bass guitarist (b. 1953)
• 2012 – Eugene Polley, American engineer, invented the remote control (b. 1915)
• 2012 – Andrew B. Steinberg, American lawyer (b. 1958)
• 2013 – Flavio Costantini, Italian painter and illustrator (b. 1926)
• 2013 – Billie Dawe, Canadian ice hockey player and manager (b. 1924)
• 2013 – Anders Eliasson, Swedish composer (b. 1947)
• 2013 – Miloslav Kříž, Czech basketball player and coach (b. 1924)
• 2013 – Ray Manzarek, American singer-songwriter, keyboard player, and producer (b. 1939)
• 2013 – Denys Roberts, English judge and politician (b. 1923)
• 2013 – Zach Sobiech, American singer-songwriter (b. 1995)
• 2014 – Sandra Bem, American psychologist and academic (b. 1944)
• 2014 – Ross Brown, New Zealand rugby player (b. 1934)
• 2014 – Robyn Denny, English-French painter (b. 1930)
• 2014 – Arthur Gelb, American journalist, author, and critic (b. 1924)
• 2014 – Prince Rupert Loewenstein, Spanish-English businessman (b. 1933)
• 2014 – Barbara Murray, English actress (b. 1929)^[45]
• 2015 – Bob Belden, American saxophonist, composer, and producer (b. 1956)
• 2015 – Femi Robinson, Nigerian actor and playwright (b. 1940)
• 2016 – Kho Jabing, Malaysian convicted murderer who was executed by hanging in Singapore (b. 1984)^[46]
• 2019 – Niki Lauda, Austrian race car driver (b. 1949)^[47]
• 2021 – Gary Wilson, American anti-pornography activist (b. 1956)^[48]
• 2022 – Roger Angell, American sportswriter and author (b. 1920)^[49]
• 2022 – Susan Roces, Filipino actress (b. 1941)^[50]
• 2024 – Ivan Boesky, American stock trader (b. 1937)^[51]

• Christian feast day:
  • Abercius and Helena
  • Alcuin of York
  • Aurea of Ostia
  • Austregisilus
  • Baudilus
  • Bernardino of Siena
  • Ivo of Chartres
  • Lucifer of Cagliari
  • Sanctan
  • May 20 (Eastern Orthodox liturgics)
• Day of Remembrance (Cambodia)
• Emancipation Day (Florida)
• European Maritime Day (European Council)
• Independence Restoration Day, celebrates the independence of East Timor from Indonesia in 2002.
• Josephine Baker Day (NAACP)
• National Awakening Day (Indonesia), and its related observances:
  • Indonesian Doctor Day (Indonesia)
• National Day (Cameroon)
• World Bee Day^[52]
• World Metrology Day

• Aung-Thwin, Michael A. (2017). Myanmar in the Fifteenth Century. Honolulu: University of Hawai'i Press. ISBN 978-0-8248-6783-6.
• Kala, U (2006) [1724]. Maha Yazawin (in Burmese). Vol. 1–3 (4th printing ed.). Yangon: Ya-Pyei Publishing.

Wikimedia Commons has media related to May 20.

• BBC: On This Day
• The New York Times: On This Day
• Historical Events on May 20