On this day: April 15

Events on April 15

• 769 The final session of the Lateran Council, convened to rectify abuses in the papal electoral process that had led to the elevation of the antipopes Constantine II and Philip, was held in Rome. Wikipedia
• 1071 Byzantine–Norman wars: After a siege of almost three years, Italo-Norman forces conquered the city of Bari, the capital of the Catepanate of Italy, ending more than five centuries of Byzantine presence in the region. Wikipedia
• 1191 Henry VI, King of Germany, was crowned Holy Roman Emperor. Wikipedia
• 1632 Thirty Years' War: A Swedish–German army defeated the forces of the Catholic League at the Battle of Rain, mortally wounding their commander Johann Tserclaes, Count of Tilly. Wikipedia
• 1738 Serse, an opera by Baroque composer George Frideric Handel loosely based on Xerxes I of Persia, premiered in London. Wikipedia
• 1755 A Dictionary of the English Language by Samuel Johnson was first published, becoming one of the most influential dictionaries in the history of English. Wikipedia
• 1802 English poet William Wordsworth and his sister Dorothy encountered a "long belt" of daffodils near Ullswater, inspiring him to pen his best-known work, "I Wandered Lonely as a Cloud". Wikipedia
• 1896 Closing ceremony of the Games of the I Olympiad in Athens, Greece. Wikipedia
• 1912 More than 1,500 people on the Titanic died when the passenger liner sank after colliding with an iceberg southeast of Newfoundland. Wikipedia
• 1922 U.S. senator John B. Kendrick introduced a resolution calling for an investigation of a secret land deal involving U.S. president Warren G. Harding's administration, leading to the Teapot Dome scandal. Wikipedia
• 1923 Ten Japanese-American children were killed in a racially motivated arson attack on a school in Sacramento, California. Wikipedia
• 1923 Insulin becomes generally available for use by people with diabetes. Wikipedia
• 1927 Torrential rains caused the Mississippi River to break out of its levee system in at least 145 places, resulting in the worst flooding in the history of the United States. Wikipedia
• 1936 The Great Arab Revolt in the British Mandate for Palestine began when unknown assailants attacked a convoy of trucks and killed two of the Jewish drivers. Wikipedia
• 1947 Jackie Robinson, the first African American to break the baseball color line, played his first game in Major League Baseball. Wikipedia
• 1952 The Boeing B-52 Stratofortress, a long-range, subsonic, jet-powered, strategic bomber operated by the U.S. Air Force for most of the aircraft's history, made its first flight. Wikipedia
• 1955 American restaurateur Ray Kroc opened the ninth McDonald's franchise in Des Plaines, Illinois, an occasion considered to be the founding of the present corporation. Wikipedia
• 1957 The Indiaman departed Victoria Coach Station, London, as part of the first UK–India bus service. Wikipedia
• 1958 On Walter O'Malley's initiative, the Los Angeles Dodgers and San Francisco Giants played the first Major League Baseball game on the U.S. West Coast. Wikipedia
• 1989 The Hillsborough disaster, a human crush that caused 97 deaths in the worst disaster in British sporting history, occurred during an FA Cup match between Liverpool and Nottingham Forest in Sheffield. Wikipedia
• 1989 The death of former Chinese General Secretary Hu Yaobang triggered a series of events that led to the Tiananmen Square protests in Beijing. Wikipedia
• 1994 At a GATT ministerial meeting in Marrakesh, Morocco, representatives of 123 countries and the European Communities signed an agreement to establish the World Trade Organization. Wikipedia
• 2002 Air China Flight 129 crashed on approach to Gimhae International Airport in Busan, South Korea, killing 129 people. Wikipedia
• 2013 Dzhokhar and Tamerlan Tsarnaev set off two pressure cooker bombs during the running of the Boston Marathon, killing three people and injuring 264 others. Wikipedia
• 2019 A fire severely damaged Notre-Dame de Paris, destroying the cathedral's timber spire and much of the roof. Wikipedia
• 2021 A mass shooting at a FedEx Ground facility in Indianapolis, Indiana, killed nine and injured seven. Wikipedia

Born on April 15

• 1452 Leonardo da Vinci, Italian painter, sculptor, and architect (died 1519) Wikipedia
• 1469 Guru Nanak, the first Sikh guru (died 1539) Wikipedia
• 1642 Suleiman II, Ottoman sultan (died 1691) Wikipedia
• 1684 Catherine I of Russia (died 1727) Wikipedia
• 1707 Leonhard Euler, Swiss mathematician and physicist (died 1783) Wikipedia
• 1832 Wilhelm Busch, German poet, painter, and illustrator (died 1908) Wikipedia
• 1843 Henry James, American novelist, short story writer, and critic (died 1916) Wikipedia
• 1858 Émile Durkheim, French sociologist, psychologist, and philosopher (died 1917) Wikipedia
• 1874 Johannes Stark, German physicist and academic, Nobel Prize laureate (died 1957) Wikipedia
• 1894 Nikita Khrushchev, Russian general and politician, 7th Premier of the Soviet Union (died 1971) Wikipedia
• 1896 Nikolay Semyonov, Russian physicist and chemist, Nobel Prize laureate (died 1986) Wikipedia
• 1907 Nikolaas Tinbergen, Dutch-English ethologist and ornithologist, Nobel Prize laureate (died 1988) Wikipedia
• 1912 Kim Il Sung, North Korean general and politician, 1st Supreme Leader of North Korea (died 1994) Wikipedia
• 1920 Richard von Weizsäcker, German soldier and politician, 6th President of Germany (died 2015) Wikipedia
• 1930 Vigdís Finnbogadóttir, Icelandic educator and politician, 4th President of Iceland Wikipedia
• 1931 Tomas Tranströmer, Swedish poet, translator, and psychologist Nobel Prize laureate (died 2015) Wikipedia
• 1938 Claudia Cardinale, Italian actress (died 2025) Wikipedia
• 1943 Robert Lefkowitz, American physician and biochemist, Nobel Prize laureate Wikipedia
• 1949 Alla Pugacheva, Russian singer-songwriter and actress Wikipedia
• 1959 Emma Thompson, English actress, comedian, author, activist and screenwriter Wikipedia
• 1961 Carol W. Greider, American molecular biologist Wikipedia
• 1990 Emma Watson, English actress Wikipedia

Died on April 15

• 1446 Filippo Brunelleschi, Italian sculptor and architect (born 1377) Wikipedia
• 1558 Hurrem Sultan, wife of Suleiman the Magnificent and the Haseki sultan of Ottoman Empire (born 1505) Wikipedia
• 1764 Madame de Pompadour, mistress of King Louis XV (born 1721) Wikipedia
• 1765 Mikhail Lomonosov, Russian chemist and physicist (born 1711) Wikipedia
• 1865 Abraham Lincoln, 16th President of the United States (born 1809) Wikipedia
• 1888 Matthew Arnold, English poet and critic (born 1822) Wikipedia
• 1912 Victims of the Titanic disaster: Wikipedia
• 1938 César Vallejo, Peruvian journalist, poet, and playwright (born 1892) Wikipedia
• 1942 Robert Musil, Austrian-Swiss author and playwright (born 1880) Wikipedia
• 1980 Jean-Paul Sartre, French philosopher and author, Nobel Prize laureate (born 1905) Wikipedia
• 1986 Jean Genet, French novelist, poet, and playwright (born 1910) Wikipedia
• 1990 Greta Garbo, Swedish-American actress (born 1905) Wikipedia
• 1998 Pol Pot, Cambodian general and politician, 29th Prime Minister of Cambodia (born 1925) Wikipedia
• 2018 R. Lee Ermey, American actor (born 1944) Wikipedia

Holidays and observances

• Christian feast day: Abbo II of Metz Wikipedia
• Christian feast day: Blessed César de Bus Wikipedia
• Christian feast day: Father Damien (Catholic and Episcopal Church) Wikipedia
• Christian feast day: Hunna Wikipedia
• Christian feast day: Paternus of Avranches Wikipedia
• Christian feast day: April 15 (Eastern Orthodox liturgics) Wikipedia
• Day of the Sun (North Korea) Wikipedia
• Father Damien Day (Hawaii) Wikipedia
• Hillsborough Disaster Memorial (Liverpool, England) Wikipedia
• Jackie Robinson Day (United States) Wikipedia
• National American Sign Language Day (United States) Wikipedia
• Pohela Boishakh (Bengali New Year; India) Wikipedia
• Tax Day, the official deadline for filing an individual tax return (or requesting an extension). (United States, Philippines) Wikipedia
• Universal Day of Culture Wikipedia

Sources

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