On this day: May 20

Events on May 20

• 325 The First Council of Nicaea, the first ecumenical council of the Christian Church, was formally opened by Constantine the Great. Wikipedia
• 685 The Picts defeated the Northumbrians at the Battle of Dun Nechtain, severely weakening the latter's power in northern Great Britain. Wikipedia
• 794 According to the Anglo-Saxon Chronicle, King Æthelberht II of East Anglia was beheaded on the orders of Offa of Mercia. Wikipedia
• 1217 First Barons' War: English forces under William Marshal defeated French troops at the Battle of Lincoln. Wikipedia
• 1498 Portuguese explorer Vasco da Gama discovers the sea route to India when he arrives at Kozhikode (previously known as Calicut), India. Wikipedia
• 1515 Ulysses, who would be famously depicted in a posthumous woodcut, landed in Lisbon, becoming the first of his species to visit Europe in a thousand years. Wikipedia
• 1609 Thomas Thorpe published the first copies of Shakespeare's sonnets, possibly without William Shakespeare's consent. Wikipedia
• 1714 J. S. Bach led the first performance of his Pentecost cantata Erschallet, ihr Lieder at the chapel of Schloss Weimar. Wikipedia
• 1811 A British squadron under Charles Marsh Schomberg defeated a French force off Tamatave, Madagascar, that was attempting to reinforce the French garrison on Mauritius. Wikipedia
• 1861 American Civil War: The State of North Carolina secedes from the Union. Wikipedia
• 1875 Representatives from seventeen countries signed the Metre Convention, which set up an institute for the purpose of coordinating international metrology and for coordinating the development of the metric system. Wikipedia
• 1927 With the signing of the Treaty of Jeddah, the United Kingdom recognized the sovereignty of Ibn Saud over Hejaz and Nejd, which later merged to become Saudi Arabia. Wikipedia
• 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. Wikipedia
• 1940 The Holocaust: The first prisoners arrive at a new concentration camp at Auschwitz. Wikipedia
• 1941 World War II: German paratroopers began the Battle of Heraklion on the island of Crete, capturing the airfield and port in Heraklion ten days later. Wikipedia
• 1943 The Luttra Woman, a bog body from the Early Neolithic period, was discovered near Luttra, Sweden. Wikipedia
• 1947 The first session of the National Diet opened in Tokyo, Japan. Wikipedia
• 1965 While attempting to land at Cairo International Airport, Pakistan International Airlines Flight 705 crashed for unknown reasons, killing all but 6 of the 121 people on board. Wikipedia
• 1983 A team of researchers led by French virologist Luc Montagnier published their discovery of HIV, but were not then certain that it caused AIDS. Wikipedia
• 1989 The Chinese authorities declare martial law in the face of pro-democracy demonstrations, setting the scene for the Tiananmen Square massacre. Wikipedia
• 1993 "One for the Road", the series finale of American television sitcom Cheers, was watched by 42.4 million American households on its original airing. Wikipedia
• 1996 In deciding Romer v. Evans, the U.S. Supreme Court struck down a constitutional amendment in Colorado that prevented protected status under the law for homosexuals or bisexuals. Wikipedia
• 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). Wikipedia
• 2012 The first of two major earthquakes struck Northern Italy, resulting in seven deaths. Wikipedia
• 2013 A tornado struck Moore, Oklahoma, United States, killing 24 people and causing an estimated $2 billion of damage. Wikipedia
• 2022 Russo-Ukrainian war: Russia claimed full control of Mariupol after a nearly three-month siege. Wikipedia

Born on May 20

• 1799 Honoré de Balzac, French novelist and playwright (died 1850) Wikipedia
• 1806 John Stuart Mill, English economist, civil servant, and philosopher (died 1873) Wikipedia
• 1822 Frédéric Passy, French economist and academic, Nobel Prize laureate (died 1912) Wikipedia
• 1860 Eduard Buchner, German chemist, zymologist, and academic, Nobel Prize laureate (died 1917) Wikipedia
• 1882 Sigrid Undset, Danish-Norwegian novelist, essayist, and translator, Nobel Prize laureate (died 1949) Wikipedia
• 1883 Faisal I of Iraq (died 1933) Wikipedia
• 1901 Max Euwe, Dutch chess player, mathematician, and author (died 1981) Wikipedia
• 1908 James Stewart, American actor (died 1997) Wikipedia
• 1915 Moshe Dayan, Israeli general and politician, 5th Israeli Minister of Foreign Affairs (died 1981) Wikipedia
• 1918 Edward B. Lewis, American biologist, geneticist, and academic, Nobel Prize laureate (died 2004) Wikipedia
• 1935 José Mujica, Uruguayan guerrilla leader and politician, 40th President of Uruguay (died 2025) Wikipedia
• 1941 Goh Chok Tong, Singaporean politician, 2nd Prime Minister of Singapore Wikipedia
• 1944 Joe Cocker, English singer-songwriter (died 2014) Wikipedia
• 1946 Cher, American singer-songwriter, producer, and actress Wikipedia
• 1952 Roger Milla, Cameroonian footballer and manager Wikipedia
• 1957 Yoshihiko Noda, Japanese lawyer and politician, 62nd Prime Minister of Japan Wikipedia
• 1968 Timothy Olyphant, American actor and producer Wikipedia
• 1972 Busta Rhymes, American rapper, producer, and actor Wikipedia
• 1981 Iker Casillas, Spanish footballer Wikipedia
• 1982 Petr Čech, Czech footballer Wikipedia
• 1985 Chris Froome, Kenyan-English cyclist Wikipedia
• 1987 Mike Havenaar, Japanese footballer Wikipedia

Died on May 20

• 1277 Pope John XXI (born 1215) Wikipedia
• 1506 Christopher Columbus, Italian explorer, early European explorer of the Americas (born 1451) Wikipedia
• 1622 Osman II, Ottoman sultan (born 1604) Wikipedia
• 1648 Władysław IV Vasa, Polish son of Sigismund III Vasa (born 1595) Wikipedia
• 1834 Gilbert du Motier, Marquis de Lafayette, French general (born 1757) Wikipedia
• 1896 Clara Schumann, German pianist and composer (born 1819) Wikipedia
• 1940 Verner von Heidenstam, Swedish author and poet, Nobel Prize laureate (born 1859) Wikipedia
• 1947 Philipp Lenard, Slovak-German physicist and academic, Nobel Prize laureate (born 1862) Wikipedia
• 1989 John Hicks, English economist and academic, Nobel Prize laureate (born 1904) Wikipedia
• 2002 Stephen Jay Gould, American paleontologist, biologist, and academic (born 1941) Wikipedia
• 2005 Paul Ricœur, French philosopher and academic (born 1913) Wikipedia
• 2013 Ray Manzarek, American singer-songwriter, keyboard player, and producer (born 1939) Wikipedia
• 2019 Niki Lauda, Austrian race car driver (born 1949) Wikipedia
• 2025 George Wendt, American actor and comedian (born 1948) Wikipedia

Holidays and observances

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

Sources

• Wikipedia — “May 20” — events, births, deaths and observances (text under CC BY-SA 4.0) (checked 2026-10-15)
• Wikipedia — “Selected anniversaries/May 20” — the anniversaries editors chose for the date and the article each one is about (checked 2026-10-15)
• Wikidata — in how many language editions each entry's own article exists, used to fill the lists (CC0) (checked 2026-10-15)
• vacanza/holidays (open-source holiday rules, MIT licence) — holiday rules used to build the lists (checked 2026-10-15)

The events, births, deaths and observances above are from the English Wikipedia article “May 20” and the articles it links to (authors and history), retrieved 2026-10-15 through the Wikimedia “On this day” feed. They are licensed under CC BY-SA 4.0; this selection is shared under the same licence. Every anniversary that Wikipedia's editors selected for May 20 stays on the list; the remaining places, up to 26 events, 22 births and 14 deaths, go to the entries whose own article — about the event itself, or else the person or thing it is about — appears in the most language editions (counted from Wikidata); an article about a person or thing, which covers far more than one day, counts half. An entry with no article of its own counts, also at half, by the least covered article it links, and one that links only places counts for nothing. Each list runs by year, and the wording is unchanged apart from removing references to pictures, audio and video.