On this day: May 21

Events on May 21

• 878 Arab–Byzantine wars: The city of Syracuse was captured by the Aghlabids as part of the Muslim conquest of Sicily. Wikipedia
• 996 Sixteen-year-old Otto III is crowned Holy Roman Emperor. Wikipedia
• 1138 The Crusades: The siege of Shaizar ended, and the Emir of Shaizar became a vassal of the Byzantine Empire. Wikipedia
• 1674 The nobility elect John Sobieski King of Poland and Grand Duke of Lithuania. Wikipedia
• 1703 English writer Daniel Defoe was imprisoned for seditious libel after publishing a pamphlet that was perceived to satirise the Tory publications about Dissenters. Wikipedia
• 1809 The first day of the Battle of Aspern-Essling between the Austrian army led by Archduke Charles and the French army led by Napoleon I of France sees the French attack across the Danube held. Wikipedia
• 1851 The Congress of Colombia passed a law abolishing slavery in the country, to take effect at the beginning of the new year. Wikipedia
• 1856 A crowd of about 800 pro-slavery Americans ransacked the town of Lawrence, Kansas. Wikipedia
• 1864 American Civil War: The inconclusive Battle of Spotsylvania Court House in Virginia ended with combined Union and Confederate casualties totaling around 31,000. Wikipedia
• 1871 French troops invade the Paris Commune and engage its residents in street fighting. By the close of "Bloody Week", some 20,000 communards have been killed and 38,000 arrested. Wikipedia
• 1881 The American Red Cross is established by Clara Barton in Dansville, New York. Wikipedia
• 1904 The Fédération Internationale de Football Association (FIFA) is founded in Paris. Wikipedia
• 1911 Mexican president Porfirio Díaz and the revolutionary Francisco I. Madero signed the Treaty of Ciudad Juárez to end hostilities between each other's forces, concluding the initial phase of the Mexican Revolution. Wikipedia
• 1917 The Imperial War Graves Commission was established by royal charter to mark, record and maintain the graves and places of commemoration of British Empire military forces. Wikipedia
• 1924 University of Chicago students Nathan Leopold Jr. and Richard Loeb murdered a 14-year-old boy in a thrill killing out of a desire to commit a "perfect crime". Wikipedia
• 1925 The opera Doktor Faust, unfinished when composer Ferruccio Busoni died, was premiered in Dresden. Wikipedia
• 1927 Aboard the Spirit of St. Louis, American aviator Charles Lindbergh completed the first solo non-stop transatlantic flight, flying from Roosevelt Field near New York City to Paris–Le Bourget Airport. Wikipedia
• 1932 Bad weather forces Amelia Earhart to land in a pasture in Derry, Northern Ireland, and she thereby becomes the first woman to fly solo across the Atlantic Ocean. Wikipedia
• 1946 While working with a mass of plutonium known as the demon core, Manhattan Project physicist Louis Slotin accidentally exposed himself to a lethal dose of hard radiation, making him the second victim of a criticality accident in history. Wikipedia
• 1991 Former Indian prime minister Rajiv Gandhi was assassinated by a suicide bomber in Sriperumbudur, Tamil Nadu. Wikipedia
• 1998 Indonesian president Suharto resigned after a collapse of support for his presidency amid economic and political crises, ending 32 years in power. Wikipedia
• 2005 The world's tallest roller coaster, Kingda Ka, opened at Six Flags Great Adventure in Jackson, New Jersey, U.S. Wikipedia
• 2006 The Republic of Montenegro holds a referendum proposing independence from the State Union of Serbia and Montenegro; 55% of Montenegrins vote for independence. Wikipedia
• 2014 A Taiwanese man carried out a stabbing spree on a Taipei Metro train, killing four people and injuring 24 others. Wikipedia
• 2015 Islamic State militants entered the ancient city of Palmyra. Wikipedia
• 2024 The Greenfield tornado, estimated to have produced winds in excess of 309 miles per hour (497 km/h), moved across Iowa. Wikipedia

Born on May 21

• 1471 Albrecht Dürer, German painter, engraver, and mathematician (died 1528) Wikipedia
• 1527 Philip II of Spain, King of Spain, Portugal, England and Ireland (died 1598) Wikipedia
• 1759 Joseph Fouché, French lawyer and politician (died 1820) Wikipedia
• 1792 Gaspard-Gustave de Coriolis, French mathematician and engineer (died 1843) Wikipedia
• 1799 Mary Anning, English paleontologist (died 1847) Wikipedia
• 1843 Charles Albert Gobat, Swiss lawyer and politician, and Nobel Prize laureate (died 1914) Wikipedia
• 1843 Louis Renault, French jurist, educator, and Nobel Prize laureate (died 1918) Wikipedia
• 1844 Henri Rousseau, French painter (died 1910) Wikipedia
• 1851 Léon Bourgeois, French police officer and politician, 64th Prime Minister of France, Nobel Prize laureate (died 1925) Wikipedia
• 1860 Willem Einthoven, Indonesian-Dutch physician, physiologist, and academic, Nobel Prize laureate (died 1927) Wikipedia
• 1895 Lázaro Cárdenas, Mexican general, president (1934–1940) and father of Cuauhtémoc Cárdenas (died 1970) Wikipedia
• 1914 Romain Gary, French novelist, diplomat, film director, aviator (died 1980) Wikipedia
• 1921 Andrei Sakharov, Russian physicist and academic, Nobel Prize laureate (died 1989) Wikipedia
• 1930 Malcolm Fraser, Australian politician, 22nd Prime Minister of Australia (died 2015) Wikipedia
• 1936 Günter Blobel, Polish-American biologist and academic, Nobel Prize laureate (died 2018) Wikipedia
• 1944 Mary Robinson, Irish lawyer and politician, President of Ireland Wikipedia
• 1959 Abdulla Yameen, Maldivian politician, 6th President of the Maldives Wikipedia
• 1960 Jeffrey Dahmer, American serial killer (died 1994) Wikipedia
• 1966 Lisa Edelstein, American actress and playwright Wikipedia
• 1972 The Notorious B.I.G., American rapper (died 1997) Wikipedia
• 1986 Mario Mandžukić, Croatian footballer Wikipedia
• 1994 Tom Daley, English diver Wikipedia

Died on May 21

• 1471 Henry VI, king of England (born 1421) Wikipedia
• 1481 Christian I, king of Denmark (born 1426) Wikipedia
• 1542 Hernando de Soto, Spanish-American explorer (born 1496) Wikipedia
• 1639 Tommaso Campanella, Italian astrologer, theologian, and poet (born 1568) Wikipedia
• 1686 Otto von Guericke, German physicist and inventor of the Magdeburg Hemispheres (born 1602) Wikipedia
• 1786 Carl Wilhelm Scheele, German-Swedish chemist and pharmacist (born 1742) Wikipedia
• 1935 Jane Addams, American activist and author, co-founded Hull House, Nobel Prize laureate (born 1860) Wikipedia
• 1935 Hugo de Vries, Dutch botanist and geneticist (born 1848) Wikipedia
• 1949 Klaus Mann, German-American novelist, playwright, and critic (born 1906) Wikipedia
• 1964 James Franck, German physicist and academic, Nobel Prize laureate (born 1882) Wikipedia
• 1973 Ivan Konev, Soviet Marshal and general (born 1897) Wikipedia
• 1991 Rajiv Gandhi, Indian politician, 6th Prime Minister of India (born 1944) Wikipedia
• 2000 Barbara Cartland, English author (born 1901) Wikipedia
• 2000 John Gielgud, English actor (born 1904) Wikipedia

Holidays and observances

• Afro-Colombian Day (Colombia) Wikipedia
• Christian feast day: Blessed Adílio Daronch and Manuel Gómez González Wikipedia
• Christian feast day: Blessed Franz Jägerstätter Wikipedia
• Christian feast day: Earliest day on which Corpus Christi can fall, while June 24 is the latest; held on Thursday after Trinity Sunday (often locally moved to Sunday). (Roman Catholic Church) Wikipedia
• Christian feast day: Eugène de Mazenod Wikipedia
• Christian feast day: Helena of Constantinople, also known as "Feast of the Holy Great Sovereigns Constantine and Helen, Equal-to-the-Apostles." (Eastern Orthodox Church, Anglican Communion) Wikipedia
• Christian feast day: Blessed Hemming of Turku Wikipedia
• Christian feast day: John Elliot (Episcopal Church) Wikipedia
• Christian feast day: Saints of the Cristero War, including Christopher Magallanes Wikipedia
• Christian feast day: May 21 (Eastern Orthodox liturgics) Wikipedia
• Circassian Day of Mourning (Circassians) Wikipedia
• Day of Patriots and Military (Hungary) Wikipedia
• Independence Day, celebrates the Montenegrin independence referendum in 2006, celebrated until the next day. (Montenegro) Wikipedia
• International Tea Day (International) Wikipedia
• Navy Day (Chile) Wikipedia
• Saint Helena Day, celebrates the discovery of Saint Helena in 1502. (Saint Helena, Ascension and Tristan da Cunha) Wikipedia
• World Day for Cultural Diversity for Dialogue and Development (International) Wikipedia

Sources

• Wikipedia — “May 21” — events, births, deaths and observances (text under CC BY-SA 4.0) (checked 2026-10-15)
• Wikipedia — “Selected anniversaries/May 21” — 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 21” 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 21 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.