|<<||Selected anniversaries for April||>>|
|An archive of historical anniversaries that appeared on the Main Page|
2020 day arrangement
- 1234 – Richard Marshal, Earl of Pembroke, was defeated by knights loyal to King Henry III of England at the Battle of the Curragh in County Kildare, Ireland.
- 1871 – The Duke of Buckingham formally opened the Brill Tramway (locomotive pictured), a short railway line to transport goods between his lands and the national rail network.
- 1918 – The United Kingdom's Royal Air Force was founded, towards the end of the First World War.
- 1970 – U.S. president Richard Nixon signed the Public Health Cigarette Smoking Act into law, requiring that a prominent warning by the surgeon general be placed on cigarette packages.
- 1513 – Spanish conquistador Juan Ponce de León sighted land, which he named La Florida, according to a popular legend while searching for the Fountain of Youth.
- 1865 – American Civil War: On the third attempt, Union forces captured Petersburg, Virginia, although Confederate officials and most of their remaining troops were able to escape.
- 1984 – Aboard Soyuz T-11, Rakesh Sharma (pictured) became the first Indian to be launched into space.
- 1992 – Bosnian War: Forty-two civilians are massacred in the town of Bijeljina in Bosnia and Herzegovina.
- 2015 – Four elderly men burgled items worth up to £200 million from a safe deposit facility in London's Hatton Garden area.
- 1860 – The Pony Express (stamp shown), a mail service that became the most direct means of long-distance communication across the United States before the first transcontinental telegraph, began operation.
- 1888 – Emma Elizabeth Smith was killed in the first of eleven unsolved murders of women that took place in or near the impoverished Whitechapel district in the East End of London.
- 1922 – Joseph Stalin became the first general secretary of the Communist Party of the Soviet Union.
- 1948 – Division of Korea: A communist uprising began on Jeju Island, eventually leading to the deaths of thousands of individuals and atrocities committed by both sides, including the violent suppression of the rebellion by South Korean forces.
- 2000 – In United States v. Microsoft Corp., Microsoft was found to have violated antitrust law by bundling the web browser Internet Explorer with its Windows operating system.
- 1460 – The University of Basel was founded as Switzerland's first university.
- 1721 – Robert Walpole (portrait shown) took office as First Lord of the Treasury, Chancellor of the Exchequer and Leader of the House of Commons, becoming Britain's first de facto prime minister.
- 1949 – Twelve nations signed the North Atlantic Treaty, establishing NATO, an organization that constitutes a system of collective defense whereby its member states agree to mutual defense in response to an attack by any external party.
- 1975 – Vietnam War: On a mission to evacuate children from South Vietnam, a U.S. Air Force plane crash-landed at Tan Son Nhut Air Base, killing 78 children and 60 others.
- 2002 – The Angolan government and UNITA rebels signed a memorandum of understanding, agreeing to follow the 1994 Lusaka Protocol and ending the 26-year-long Angolan Civil War.
- 919 – The Fatimid Caliphate began a second unsuccessful invasion of Egypt, then under Abbasid rule.
- 1847 – Birkenhead Park (pictured), generally acknowledged as the world's first publicly funded civic park, opened in Birkenhead, England.
- 1936 – During the second deadliest tornado outbreak in U.S. history, an F5 tornado struck Tupelo, Mississippi, killing at least 216 people.
- 1976 – The Tiananmen Incident, a protest against the Chinese regime triggered by the death of Premier Zhou Enlai near the end of the Cultural Revolution, took place in Tiananmen Square in Beijing.
- 2000 – Before a semi-final of the UEFA Cup in Istanbul, Turkey, fan violence broke out, resulting in two Leeds United supporters being stabbed to death and Galatasaray supporters being banned from attending the second leg in England.
- 1712 – A group of 23 slaves in New York City revolted, setting fire to a building, but were soon recaptured.
- 1896 – The first modern Olympic Games (official report cover shown) opened in Athens, with athletes from 14 nations participating in 43 events.
- 1945 – Second World War: The Battle of Slater's Knoll on Bougainville Island concluded with a decisive victory for the Australian Army's 7th Brigade against the Imperial Japanese Army's 6th Division.
- 1970 – Four California Highway Patrol officers were killed in a shootout following a traffic stop in Newhall, north of Los Angeles.
- 2010 – Naxalite–Maoist insurgency: Insurgents from the Communist Party of India (Maoist) ambushed a Central Reserve Police Force convoy in Dantewada district, India, killing 76 officers.
- 1141 – The Anarchy: Empress Matilda became the first female claimant to the throne of England, adopting the title "Lady of the English" after failing to be crowned in place of her cousin Stephen.
- 1724 – Johann Sebastian Bach premiered his St John Passion, a musical setting of the Passion of Jesus, at Good Friday Vespers in St. Nicholas Church, Leipzig.
- 1945 – World War II: U.S. forces sank the Japanese battleship Yamato (pictured), then the largest in the world, during Operation Ten-Go in the East China Sea.
- 1995 – First Chechen War: Russian paramilitary troops began a massacre of hundreds of civilians in Samashki, Chechnya.
- 2010 – Violent protests started in the Kyrgyz capital Bishkek in response to perceived corruption and rising living expenses, eventually resulting in the collapse of President Kurmanbek Bakiyev's government.
- 876 – Abbasid forces decisively defeated those of the Saffarid emir Ya'qub ibn Laith, forcing the latter to halt his advance into Iraq.
- 1630 – Kiliaen van Rensselaer purchased land near present-day Albany, New York, to found the Manor of Rensselaerswyck, which became the most successful patroonship under the Dutch West India Company system.
- 1911 – American cartoonist Winsor McCay released the silent short film Little Nemo (featured), one of the earliest animated films.
- 1968 – BOAC Flight 712 experienced an engine fire shortly after take-off from London Heathrow, leading to the deaths of five people on board, including flight attendant Jane Harrison, who was posthumously awarded a George Cross for heroism.
- 2013 – Two Sunni Muslim extremist groups, the Islamic State of Iraq and the Al-Nusra Front, merged to become the Islamic State of Iraq and the Levant.
- 1860 – Édouard-Léon Scott de Martinville recorded himself singing "Au clair de la lune" on his phonautograph, producing the oldest known recording of an audible human voice.
- 1940 – During the German invasion of Norway, Vidkun Quisling attempted to seize power in the first coup to be broadcast over radio.
- 1945 – The German heavy cruiser Admiral Scheer, the most successful capital-ship surface raider of the Second World War, was sunk by British bombers.
- 1980 – Iraqi philosopher Muhammad Baqir al-Sadr (pictured) and his sister Amina were executed by the regime of Saddam Hussein.
- 2005 – Charles, Prince of Wales, married Camilla Parker Bowles in a civil ceremony at the Windsor Guildhall.
- 1809 – Napoleonic Wars: The War of the Fifth Coalition began with the Austrian invasion of Bavaria, then a client state of France.
- 1925 – The novel The Great Gatsby by American author F. Scott Fitzgerald (pictured) was first published by Scribner's.
- 1944 – The Holocaust: Slovak Jewish prisoners Rudolf Vrba and Alfréd Wetzler escaped from Auschwitz, later publishing a report that became one of the earliest and most detailed descriptions of the camp's mass killings.
- 1970 – In the midst of business disagreements with his bandmates, Paul McCartney announced his departure from the Beatles.
- 1992 – Nagorno-Karabakh War: Dozens of Armenian civilians were massacred in the village of Maraga by Azerbaijani forces.
- 1241 – Mongol invasion of Europe: Mongol forces led by Batu Khan and Subutai defeated the army of King Béla IV at the Battle of Mohi near the river Sajó, a key victory in their first invasion of Hungary.
- 1713 – The main treaties of the Peace of Utrecht were signed in the city of Utrecht in the Dutch Republic, helping to bring an end to the War of the Spanish Succession.
- 1913 – The cricket pavilion at the Nevill Ground was destroyed in an arson attack (damage pictured) that was attributed to militant suffragettes as part of a country-wide campaign co-ordinated by the Women's Social and Political Union.
- 1979 – Uganda–Tanzania War: The allied forces of Tanzania and the Uganda National Liberation Front captured the capital Kampala, deposing Ugandan president Idi Amin.
- 1993 – Prisoners at the Southern Ohio Correctional Facility near Lucasville, Ohio, rioted and took over the prison for 11 days, resulting in the deaths of one officer and nine inmates.
- 627 – King Edwin of Northumbria was baptised by Bishop Paulinus of York.
- 1822 – Greek War of Independence: Ottoman troops began a massacre of tens of thousands of Greeks on the island of Chios.
- 1910 – SMS Zrínyi, one of the last pre-dreadnoughts built by the Austro-Hungarian Navy, was launched.
- 1980 – Canadian athlete Terry Fox (pictured) embarked on an east–west "Marathon of Hope" with a prosthetic leg, beginning in St. John's, Newfoundland and Labrador, and intending to reach Vancouver, to raise funds for cancer research.
- 2014 – A fire broke out in the hills near Valparaíso, Chile, eventually destroying at least 2,500 homes and leaving approximately 11,000 people homeless.
- 1204 – Troops of the Fourth Crusade entered Constantinople and began a sack of the city, temporarily dissolving the Byzantine Empire.
- 1829 – The Roman Catholic Relief Act received royal assent, removing the most substantial restrictions on Catholics in the United Kingdom.
- 1943 – The Neoclassical Jefferson Memorial (pictured) in Washington, D.C., was formally dedicated on the 200th anniversary of Thomas Jefferson's birth.
- 1976 – Forty people died in an explosion at an ammunition factory in Lapua, Finland.
- 1984 – Kashmir conflict: Indian forces launched a pre-emptive attack on the disputed Siachen Glacier region of Kashmir, triggering a military conflict with Pakistan.
- 43 BC – Mark Antony's forces initially had the upper hand in the Battle of Forum Gallorum, but were forced to retreat by a counter-attack by Roman Republican legions.
- 966 – Mieszko I, ruler of the Polans, converted to Christianity, an event considered to be the founding of the Polish state.
- 1935 – Dust Bowl: A severe dust storm (pictured) swept across Oklahoma and northern Texas, removing an estimated 300 million tons of topsoil from the prairies.
- 2010 – Nearly 2,700 people were killed in an earthquake registering 6.9 Mw in Yushu Tibetan Autonomous Prefecture, China.
- 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.
- 1802 – English poet William Wordsworth and his sister Dorothy encountered a "long belt" of daffodils while walking around Ullswater in the Lake District, inspiring him to pen his best-known work, "I Wandered Lonely as a Cloud".
- 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.
- 2019 – A fire (pictured) severely damaged the Notre-Dame de Paris cathedral, destroying the building's timber spire and much of its roof.
- 1520 – Citizens of Toledo, Castile, opposed to the rule of the foreign-born Charles I, revolted when the royal government attempted to unseat radical city councilors.
- 1853 – The first passenger train of the Great Indian Peninsula Railway, a predecessor of the modern-day Indian Railways, travelled from Bombay to Tanna.
- 1963 – In response to an open letter written by white clergymen four days earlier, Martin Luther King Jr. (pictured) wrote the Letter from Birmingham Jail, defending the strategy of nonviolent resistance against racism.
- 2014 – The ferry MV Sewol sank 1.5 km (0.93 mi) off Donggeochado, South Korea, killing 304 of 476 passengers on board, most of whom were students from Danwon High School.
- 1362 – Lithuanian Crusade: After a month-long siege, forces of the Teutonic Order captured and destroyed Kaunas Castle (reconstruction pictured), which was defended by troops of the Grand Duchy of Lithuania.
- 1797 – French Revolutionary Wars: British forces commanded by Lieutenant-General Ralph Abercromby invaded the Spanish colonial port of San Juan, Puerto Rico.
- 1869 – The Free and Sovereign State of Morelos, named after José María Morelos, the hero of the Siege of Cuautla, was admitted as the 27th state of Mexico.
- 1951 – The Peak District was designated the first national park in the United Kingdom.
- 1975 – The Khmer Rouge captured Phnom Penh, the capital of the Khmer Republic, ending the Cambodian Civil War and establishing the socialist state of Democratic Kampuchea.
- 1689 – Glorious Revolution: Provincial militia and citizens in Boston revolted, arresting officials of the Dominion of New England.
- 1738 – By royal decree, King Philip V established the Real Academia de la Historia, tasked with studying the history of Spain.
- 1949 – The Republic of Ireland Act 1948 came into force, declaring Ireland a republic and terminating its membership of the British Commonwealth of Nations.
- 1958 – Controversial American poet Ezra Pound was released from St. Elizabeths Hospital, a psychiatric hospital in Washington, D.C., in which he had been incarcerated for twelve years.
- 1980 – Robert Mugabe (pictured) took the oath of office to become the first prime minister of Zimbabwe upon the country's independence from the United Kingdom.
- AD 65 – The freedman Milichus betrayed Gaius Calpurnius Piso's plot to kill Roman emperor Nero, leading to the arrest of the conspirators.
- 1713 – With no living male heirs, Charles VI, Holy Roman Emperor, issued the Pragmatic Sanction, which allowed daughters to inherit the Habsburg hereditary possessions.
- 1903 – Anti-Jewish riots broke out in Kishinev, the capital of Bessarabia Governorate, causing the death of nearly 50 Jews and focusing worldwide attention on the persecution of Jews in Russia.
- 1984 – "Advance Australia Fair", written by Scottish-born composer Peter Dodds McCormick, officially replaced "God Save the Queen" as Australia's national anthem.
- 1995 – A truck bomb destroyed much of the Alfred P. Murrah Federal Building (damage pictured) in Oklahoma City, Oklahoma, killing 168 people and injuring more than 680 others.
- 1535 – Sun dogs were observed over Stockholm, Sweden, inspiring the painting Vädersolstavlan, the oldest colour depiction of the city.
- 1809 – War of the Fifth Coalition: Commanded by Napoleon, Franco-German forces defeated a reinforced Austrian corps at the Battle of Abensberg.
- 1939 – Billie Holiday (pictured) recorded the song "Strange Fruit", which later became an emblem of the civil rights movement.
- 1968 – Pierre Trudeau was sworn in as prime minister of Canada, succeeding Lester B. Pearson.
- 2010 – An explosion on Deepwater Horizon, an offshore rig in the Gulf of Mexico, resulted in the largest marine oil spill in history.
- 1836 – Forces of the Republic of Texas led by Sam Houston (pictured) defeated the Mexican troops of General Antonio López de Santa Anna in the Battle of San Jacinto, the decisive battle in the Texas Revolution.
- 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.
- 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.
- 2010 – Ukraine and Russia signed the Kharkiv Pact, extending the Russian lease on naval facilities in Crimea.
- 1500 – Pedro Álvares Cabral's fleet anchored off the coast of present-day Brazil, claiming the land for the Portuguese Empire.
- 1864 – The U.S. Congress authorized the creation of a two-cent coin (pictured), the first U.S. currency to bear the phrase "In God We Trust".
- 1915 – World War I: German forces released 168 tons of chlorine gas at the beginning of the Second Battle of Ypres, causing thousands of casualties among French troops.
- 1969 – British yachtsman Robin Knox-Johnston completed the first single-handed non-stop circumnavigation of the world, winning the Sunday Times Golden Globe Race.
- 2000 – In a pre-dawn raid, U.S. federal agents seized six-year-old Elián González from his relatives' home in Miami and returned him to his Cuban father.
- 1014 – Forces led by Brian Boru, High King of Ireland, defeated an alliance of Viking and Irish troops at the Battle of Clontarf, which ended with Brian's death.
- 1661 – Charles II was crowned King of England, Scotland and Ireland at Westminster Abbey in London.
- 1920 – The Grand National Assembly of Turkey, the country's unicameral legislature, first met in Ankara in the midst of the Turkish War of Independence.
- 1954 – Batting for the Milwaukee Braves against Vic Raschi of the St. Louis Cardinals, Hank Aaron (pictured) hit the first of his 755 home runs in Major League Baseball.
- 2010 – Arizona governor Jan Brewer signed into law the controversial anti–illegal immigration bill SB 1070, much of which was later struck down by the U.S. Supreme Court.
- 1479 BC – Thutmose III became the sixth pharaoh of the Eighteenth Dynasty of Egypt, with his aunt and stepmother Hatshepsut as coregent.
- 1866 – German composer Max Bruch conducted the premiere of his first violin concerto, which later became his most famous work.
- 1913 – The Woolworth Building in New York City officially opened; at the time, it was the tallest building in the world, with a height of 792 ft (241 m).
- 1965 – Cold War: The Dominican Civil War broke out due to tensions following a military coup of the democratically elected government of President Juan Bosch two years earlier.
- 1990 – The Hubble Space Telescope (pictured) was launched aboard STS-31 by Space Shuttle Discovery.
- 775 – The Abbasid army won a decisive victory over the forces of rebelling Armenian princes at the Battle of Bagrevand.
- 1846 – Mexican–American War: Mexican forces defeated American troops over the disputed border of Texas, later serving as the primary justification for the U.S. Congress's declaration of war on Mexico.
- 1920 – At the San Remo conference, the principal Allies of World War I passed a resolution allocating League of Nations mandates for the administration of former Ottoman territories in the Middle East.
- 1960 – The U.S. Navy submarine USS Triton (pictured) completed the first submerged circumnavigation of the world.
- 1974 - The Carnation Revolution took place in Portugal ending the 48 year long autoritarian dictatorship( Estado Novo (Portugal) ).
- 1990 – Violeta Chamorro took office as president of Nicaragua, becoming the first female head of state in the Americas to have been elected in her own right.
- 1478 – In a conspiracy to replace the Medici family as rulers of the Republic of Florence, the Pazzi family attacked Lorenzo de' Medici (portrait shown) and killed his brother Giuliano during Mass.
- 1944 – World War II: U.S. Navy submarines began attacks on Japan's Take Ichi convoy as it sailed in waters between Taiwan and the Philippines, eventually sinking four vessels and killing more than 4,000 troops.
- 1970 – The World Intellectual Property Organization (WIPO) came into being when the WIPO Convention entered into force.
- 2007 – Controversy surrounding the relocation of the Bronze Soldier of Tallinn, a Soviet Red Army World War II memorial in Tallinn, Estonia, erupted into mass protests and riots.
- 1521 – Filipino natives led by chieftain Lapu-Lapu killed Portuguese explorer Ferdinand Magellan at the Battle of Mactan.
- 1650 – Wars of the Three Kingdoms: Covenanter forces defeated an invading Royalist army at the Battle of Carbisdale near the village of Culrain, Scotland.
- 1945 – The photograph Raising the Flag on the Three-Country Cairn (pictured) was taken after German troops withdrew to Norway on the last day of the Second World War in Finland, ending the Lapland War.
- 2005 – The Airbus A380, the largest passenger airliner in the world, made its maiden flight from Toulouse, France.
- 224 – The ancient Iranian Parthian Empire fell to the Sasanids after its forces were defeated at the Battle of Hormozdgan.
- 1789 – Near the island of Tofua, Fletcher Christian, acting lieutenant on board the Royal Navy ship Bounty, led a mutiny against the commander, William Bligh.
- 1923 – The 1923 FA Cup Final between Bolton Wanderers and West Ham United was held on the opening day (crowd and police pictured) of the Empire Stadium in London.
- 2008 – The 1,388-foot-tall (423.2 m) Trump International Hotel and Tower in Chicago, the building with the world's highest residence above ground level at the time, held its grand opening.
- 1770 – On his first voyage, British explorer James Cook and the crew of HMS Endeavour (replica pictured) landed at Botany Bay near present-day Sydney, making the first recorded European contact with the eastern coast of Australia.
- 1903 – A rockslide buried the Canadian mining town of Frank under more than 110 million tonnes (120 million short tons) of rock, killing at least 70 people.
- 1945 – World War II: The U.S. Army liberated Dachau, the first Nazi concentration camp, and killed German prisoners of war.
- 1970 – Vietnam War: South Vietnamese forces began the Cambodian campaign, aiming to attack North Vietnamese jungle bases.
- 2015 – The ringleaders of the Bali Nine were executed in Indonesia for attempting to smuggle 8.3 kg (18 lb) of heroin to Australia in 2005.
- 313 – Civil wars of the Tetrarchy: An outnumbered army led by Roman emperor Licinius defeated his rival Maximinus II's forces at the Battle of Tzirallum.
- 1598 – King Henry IV of France issued the Edict of Nantes, granting freedom of religion to the Huguenots.
- 1927 – The Federal Industrial Institute for Women opened near Alderson, West Virginia, as the first federal prison for women in the United States.
- 1945 – World War II: As Allied forces closed in on Berlin, Adolf Hitler and Eva Braun committed suicide in the Führerbunker one day after their marriage.
- 2000 – Faustina Kowalska (portrait shown), a Polish nun whose apparitions of Jesus inspired the Catholic devotion to the Divine Mercy, was canonized by Pope John Paul II.