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What happened on April 21
Every April 21 carries a layer of history: wars that began or ended, inventions, premieres, treaties, and people born or lost on this day across the centuries. We gathered 12 of the most striking events recorded on April 21, plus notable births and deaths, each with its year and a link to the Wikipedia article where the story continues. It is a fast way to answer "what happened on April 21" without digging through many sources: the list arrives ranked by relevance and dated.
Notable events
| Year | Event |
|---|---|
| 2021 | The Indonesian Navy submarine Nanggala imploded and sank in the Bali Sea, resulting in the deaths of all 53 people on board. Indonesian Navy |
| 2014 | The city of Flint, Michigan, U.S., changed its water source to the Flint River, which exposed residents to lead poisoning.a Flint, Michigan |
| 2010 | Ukraine and Russia signed the Kharkiv Pact, extending the Russian lease on naval facilities in Crimea. Kharkiv Pact |
| 1975 | South Vietnamese president Nguyễn Văn Thiệu resigned on hearing of the fall of Xuân Lộc, the last battle of the Vietnam War. South Vietnam |
| 1970 | In response to a dispute over wheat production quotas, Leonard Casley declared his 75 km2 (29 sq mi) farm in Western Australia to be an independent country as the Hutt River Province. Western Australia |
| 1967 | A violent tornado strikes multiple schools and destroys houses in Belvidere, Illinois, United States, causing over 450 casualties. 1967 Belvidere tornado |
| 1962 | The Century 21 Exposition, the first world's fair in the United States since World War II, opened in Seattle. Century 21 Exposition |
| 1960 | BrasÃlia, a planned city primarily designed by architect and urban planner Lúcio Costa, was officially inaugurated, replacing Rio de Janeiro as the capital of Brazil. BrasÃlia |
| 1958 | United Airlines Flight 736 collided with a U.S. Air Force fighter jet over southern Nevada, resulting in the deaths of all 49 people on board both aircraft. United Air Lines Flight 736 |
| 1836 | Forces of the Republic of Texas led by Sam Houston defeated the Mexican troops of Antonio López de Santa Anna in the Battle of San Jacinto, the decisive and final battle of the Texas Revolution. Republic of Texas |
| 1789 | The Ladies of Trenton social club hosted a reception for President-elect George Washington as he journeyed to New York City for his first inauguration. George Washington's reception at Trenton |
| 1725 | J. S. Bach's cantata Bleib bei uns, denn es will Abend werden, was first performed on Easter Monday. Johann Sebastian Bach |
Births
| Year | Who |
|---|---|
| 2008 | Hyein, South Korean singer Hyein |
| 2007 | Princess Isabella of Denmark, daughter of King Frederik X and Queen Mary of Denmark Princess Isabella of Denmark |
| 2003 | Xavi Simons, Dutch footballer Xavi Simons |
| 1999 | Choi Hyun-suk, South Korean rapper Choi Hyun-suk |
Deaths
| Year | Who |
|---|---|
| 2025 | Pope Francis (born 1936) Pope Francis |
| 2024 | Terry A. Anderson, American journalist (born 1947) Terry A. Anderson |
| 2019 | Polly Higgins, Scottish barrister, author and environmental lobbyist (born 1968) Polly Higgins |
| 2017 | Ugo Ehiogu, English footballer (born 1972) Ugo Ehiogu |
A single anniversary does not explain on its own why a day matters: one April 21 can hold a scientific milestone, a tragedy and the birth of an artist, centuries apart. That is why we date every row and link the source, so you can follow what interests you. The selection mixes 12 events, 4 births and 4 deaths; the full list, with every reference, lives on Wikipedia.
Source, license and method
This page curates the day's anniversaries for April 21 from Wikipedia, delivered through the Wikimedia "On this day" feed (the encyclopedia's own open dataset). It is not original research: the facts, years and wording come from Wikipedia and are licensed under Creative Commons Attribution ShareAlike (CC BY-SA 4.0), which requires crediting the source and keeping the same license. We pick each day's most relevant items, favouring the editors' own selection and the most prominent articles, and every row links back to the matching entry. For the full list and primary references, see the day's article on Wikipedia (April 21).
Continue in the dates cluster
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Last updated: · Methodology and sources