May 28
- 585 BC – A solar eclipse occurs, as predicted by Greek philosopher and scientist Thales, while Alyattes is battling Cyaxares in the Battle of the Eclipse, leading to a truce. This is one of the cardinal dates from which other dates can be calculated.
- 1503 – James IV of Scotland and Margaret Tudor are married according to a Papal Bull by Pope Alexander VI. A Treaty of Everlasting Peace between Scotland and England signed on that occasion results in a peace that lasts ten years.
- 1533 – The Archbishop of Canterbury Thomas Cranmer declares the marriage of King Henry VIII of England to Anne Boleyn valid.
- 1588 – The Spanish Armada, with 130 ships and 30,000 men, sets sail from Lisbon heading for the English Channel. (It will take until May 30 for all ships to leave port).
- 1644 – Bolton Massacre by Royalist troops under the command of the Earl of Derby.
- 1754 – French and Indian War: in the first engagement of the war, Virginia militia under 22-year-old Lieutenant Colonel George Washington defeat a French reconnaissance party in the Battle of Jumonville Glen in what is now Fayette County in southwestern Pennsylvania.
- 1798 – The United States Congress empowers president John Adams to enlist 10,000 men for service in case of a declaration of war or invasion of the country's domain. It also authorizes Adams to instruct commanders of ships-of-war to seize armed French vessels preying upon or attacking American merchantmen about the coast.
- 1830 – President Andrew Jackson signs the Indian Removal Act which relocates Native Americans.
- 1863 – American Civil War: The 54th Massachusetts Volunteer Infantry, the first African American regiment, leaves Boston, Massachusetts, to fight for the Union.
- 1892 – In San Francisco, California, John Muir organizes the Sierra Club.
- 1905 – Russo-Japanese War: The Battle of Tsushima ends with the destruction of the Russian Baltic Fleet by Admiral Togo Heihachiro and the Imperial Japanese Navy.
- 1918 – The Azerbaijan Democratic Republic and the Democratic Republic of Armenia declare their independence.
- 1926 – 28th May 1926 coup d'état: Ditadura Nacional is established in Portugal to suppress the unrest of the First Republic.
- 1930 – The Chrysler Building in New York City officially opens.
- 1934 – Near Callander, Ontario, the Dionne quintuplets are born to Oliva and Elzire Dionne; they will be the first quintuplets to survive infancy.
- 1936 – Alan Turing submits On Computable Numbers for publication.
- 1937 – The Golden Gate Bridge in San Francisco, California, is officially opened by President Franklin D. Roosevelt in Washington, D.C., who pushes a button signaling the start of vehicle traffic over the span.
- 1940 – World War II: Belgium surrenders to Germany to end the Battle of Belgium.
- 1940 – World War II: Norwegian, French, Polish and British forces recapture Narvik in Norway. This is the first allied infantry victory of the War.
- 1942 – World War II: in retaliation for the assassination of Reinhard Heydrich, Nazis in Czechoslovakia kill over 1,800 people.
- 1952 – The women of Greece are given the right to vote.
- 1961 – Peter Benenson's article The Forgotten Prisoners is published in several internationally read newspapers. This will later be thought of as the founding of the human rights organization Amnesty International.
- 1964 – The Palestine Liberation Organization is formed.
- 1974 – Northern Ireland's power-sharing Sunningdale Agreement collapses following a general strike by loyalists.
- 1975 – Fifteen West African countries sign the Treaty of Lagos, creating the Economic Community of West African States.
- 1977 – In Southgate, Kentucky, the Beverly Hills Supper Club is engulfed in fire, killing 165 people inside.
- 1979 – Constantine Karamanlis signs the full treaty of the accession of Greece with the European Economic Community.
- 1982 – Falklands War: British forces defeat the Argentines at the Battle of Goose Green.
- 1987 – 19-year-old West German pilot Mathias Rust evades Soviet Union air defenses and lands a private plane in the Red Square in Moscow. He is immediately detained and will not be released until August 3, 1988.
- 1991 – The capital city of Addis Ababa, falls to the Ethiopian People's Revolutionary Democratic Front, ending both the Derg regime in Ethiopia and the Ethiopian Civil War.
- 1993 – Eritrea and Monaco join the United Nations.
- 1995 – The Russian town of Neftegorsk is hit by a 7.6 magnitude earthquake that kills at least 2,000 people, half of the total population.
- 1996 – U.S. President Bill Clinton's former business partners in the Whitewater land deal, James McDougal and Susan McDougal, and the Governor of Arkansas Jim Guy Tucker, are convicted of fraud.
- 1998 – Nuclear testing: Pakistan responds to a series of nuclear tests by India with five of its own, prompting the United States, Japan, and other nations to impose economic sanctions.
- 1999 – In Milan, Italy, after 22 years of restoration work, Leonardo da Vinci's masterpiece The Last Supper is put back on display.
- 2002 – NATO declares Russia a limited partner in the Western alliance.
- 2002 – The Mars Odyssey finds signs of large ice deposits on the planet Mars.
- 2003 – Peter Hollingworth becomes the first Governor-General of Australia to resign his office as a result of criticism of his conduct.
- 2004 – The Iraqi Governing Council chooses Ayad Allawi, a longtime anti-Saddam Hussein exile, as prime minister of Iraq's interim government.
- 2008 – The first meeting of the Constituent Assembly of Nepal formally declares Nepal a republic, ending the 240-year reign of the Shah dynasty.
- 2010 – In West Bengal, India, a train derailment and subsequent collision kills 141 passengers.
May 27
- 927 – Battle of the Bosnian Highlands: the Croatian army, led by King Tomislav, defeats the Bulgarian Army.
- 1120 – Richard III of Capua is anointed as Prince two weeks before his untimely death.
- 1153 – Malcolm IV becomes King of Scotland.
- 1703 – Tsar Peter the Great founds the city of Saint Petersburg.
- 1798 – The Battle of Oulart Hill takes place in Wexford, Ireland.
- 1799 – War of the Second Coalition: Austrian forces defeats the French at Winterthur, Switzerland, securing control of the northeastern Swiss Plateau because of the town's location at the junction of seven cross-roads.
- 1812 – Bolivian War of Independence: In Bolivia, the Battle of La Coronilla, in which the women from Cochabamba fight against the Spanish army.
- 1813 – War of 1812: In Canada, American forces capture Fort George.
- 1849 – The Great Hall of Euston station in London is opened.
- 1860 – Giuseppe Garibaldi begins his attack on Palermo, Sicily, as part of the Italian Unification.
- 1863 – American Civil War: First Assault on the Confederate works at the Siege of Port Hudson.
- 1883 – Alexander III is crowned Tsar of Russia.
- 1896 – The F4-strength St. Louis-East St. Louis Tornado hits in St. Louis, Missouri and East Saint Louis, Illinois, killing at least 255 people and causing $2.9 billion in damage (1997 USD).
- 1905 – Russo-Japanese War: The Battle of Tsushima begins.
- 1907 – Bubonic plague breaks out in San Francisco, California.
- 1919 – The NC-4 aircraft arrives in Lisbon after completing the first transatlantic flight.
- 1927 – The Ford Motor Company ceases manufacture of the Ford Model T and begins to retool plants to make the Ford Model A.
- 1930 – The 1,046 feet (319 m) Chrysler Building in New York City, the tallest man-made structure at the time, opens to the public.
- 1933 – New Deal: The U.S. Federal Securities Act is signed into law requiring the registration of securities with the Federal Trade Commission.
- 1933 – The Walt Disney Company releases the cartoon Three Little Pigs, with its hit song "Who's Afraid of the Big Bad Wolf?"
- 1933 – The Century of Progress World's Fair opens in Chicago, Illinois.
- 1935 – New Deal: The Supreme Court of the United States declares the National Industrial Recovery Act to be unconstitutional in A.L.A. Schechter Poultry Corp. v. United States, (295 U.S. 495).
- 1937 – In California, the Golden Gate Bridge opens to pedestrian traffic, creating a vital link between San Francisco and Marin County, California.
- 1940 – World War II: In the Le Paradis massacre, 99 soldiers from a Royal Norfolk Regiment unit are shot after surrendering to German troops. Two survive.
- 1941 – World War II: U.S. President Franklin D. Roosevelt proclaims an "unlimited national emergency".
- 1941 – World War II: The German battleship Bismarck is sunk in the North Atlantic killing almost 2,100 men.
- 1942 – World War II: In Operation Anthropoid, Reinhard Heydrich is assassinated in Prague.
- 1957 – Toronto's CHUM-AM, (1050 kHz) becomes Canada's first radio station to broadcast only top 40 Rock n' Roll music format.
- 1958 – The F-4 Phantom II makes its first flight.
- 1960 – In Turkey, a military coup removes President Celal Bayar and the rest of the democratic government from office.
- 1962 – The Centralia, Pennsylvania mine fire starts.
- 1965 – Vietnam War: American warships begin the first bombardment of National Liberation Front targets within South Vietnam.
- 1967 – Australians vote in favor of a constitutional referendum granting the Australian government the power to make laws to benefit Indigenous Australians and to count them in the national census.
- 1967 – The U.S. Navy aircraft carrier USS John F. Kennedy is launched by Jacqueline Kennedy and her daughter Caroline.
- 1968 – The meeting of the Union Nationale des Étudiants de France (National Union of the Students of France) takes place. 30,000 to 50,000 people gather in the Stade Sebastien Charlety.
- 1971 – The Dahlerau train disaster, the worst railway accident in West Germany, kills 46 people and injures 25 near Wuppertal.
- 1975 – The Dibble's Bridge coach crash near Grassington, North Yorkshire, England kills 32 – the highest ever death toll in a road accident in the United Kingdom.
- 1980 – The Gwangju Massacre: Airborne and army troops of South Korea retake the city of Gwangju from civil militias, killing at least 207 and possibly many more.
- 1995 – In Culpeper, Virginia, actor Christopher Reeve is paralyzed from the neck down after falling from his horse in a riding competition.
- 1996 – First Chechnya War: Russian President Boris Yeltsin meets with Chechnyan rebels for the first time and negotiates a cease-fire.
- 1997 – The U.S. Supreme Court rules that Paula Jones can pursue her sexual harassment lawsuit against President Bill Clinton while he is in office.
- 1998 – Oklahoma City bombing: Michael Fortier is sentenced to 12 years in prison and fined $200,000 for failing to warn authorities about the terrorist plot.
- 1999 – The International Criminal Tribunal for the former Yugoslavia in The Hague, Netherlands indicts Slobodan Milošević and four others for war crimes and crimes against humanity committed in Kosovo.
- 2005 – Australian Schapelle Corby is sentenced to 20 years imprisonment in Kerobokan Prison for drug smuggling by a court in Indonesia.
- 2006 – The May 2006 Java earthquake strikes at 5:53:58 AM local time (22:53:58 UTC May 26) devastating Bantul and the city of Yogyakarta killing over 6,600 people.
May 26
- 17 – Germanicus returns to Rome as a conquering hero; he celebrates a triumph for his victories over the Cherusci, Chatti and other German tribes west of the Elbe.
- 451 – Battle of Avarayr between Armenian rebels and the Sassanid Empire takes place. The Empire defeats the Armenians militarily but guarantees them freedom to openly practice Christianity.
- 1135 – Alfonso VII of León and Castile is crowned in the Cathedral of Leon as Imperator totius Hispaniae, "Emperor of all of Spain".
- 1293 – An earthquake strikes Kamakura, Kanagawa, Japan, killing about 30,000.
- 1328 – William of Ockham, Franciscan Minister-General Michael of Cesena and two other Franciscan leaders secretly leave Avignon, fearing a death sentence from Pope John XXII.
- 1538 – Geneva expels John Calvin and his followers from the city. Calvin lives in exile in Strasbourg for the next three years.
- 1637 – Pequot War: A combined Protestant and Mohegan force under English Captain John Mason attacks a Pequot village in Connecticut, massacring approximately 500 Native Americans.
- 1647 – Alse Young, hanged in Hartford, Connecticut, becomes the first person executed as a witch in the British American colonies.
- 1736 – Battle of Ackia: British and Chickasaw soldiers repel a French and Choctaw attack on the Chickasaw village of Ackia, near present-day Tupelo, Mississippi. The French, under Louisiana governor Jean Baptiste Le Moyne, Sieur de Bienville, had sought to link Louisiana with Acadia and the other northern colonies of New France.
- 1770 – The Orlov Revolt, an attempt to revolt against the Ottoman Empire before the Greek War of Independence, ends in disaster for the Greeks.
- 1783 – A Great Jubilee Day held at Trumbull, Connecticut celebrated end of fighting in American Revolution.
- 1805 – Napoléon Bonaparte assumes the title of King of Italy and is crowned with the Iron Crown of Lombardy in the Duomo di Milano, the gothic cathedral in Milan.
- 1822 – 116 people die in the Grue Church fire, the biggest fire disaster in Norway's history.
- 1828 – Feral child Kaspar Hauser is discovered wandering the streets of Nuremberg.
- 1830 – The Indian Removal Act is passed by the U.S. Congress; it is signed into law by President Andrew Jackson two days later.
- 1857 – Dred Scott is emancipated by the Blow family, his original owners.
- 1864 – Montana is organized as a United States territory.
- 1865 – American Civil War: Confederate General Edmund Kirby Smith, commander of the Confederate Trans-Mississippi division, is the last general of the Confederate Army to surrender, at Galveston, Texas.
- 1868 – The impeachment trial of U.S. President Andrew Johnson ends with Johnson being found not guilty by one vote.
- 1869 – Boston University is chartered by the Commonwealth of Massachusetts.
- 1879 – Russia and the United Kingdom sign the Treaty of Gandamak establishing an Afghan state.
- 1896 – Nicholas II becomes Tsar of Russia.
- 1896 – Charles Dow publishes the first edition of the Dow Jones Industrial Average.
- 1897 – Dracula, a novel by Irish author Bram Stoker is published.
- 1906 – Vauxhall Bridge is opened in London.
- 1908 – At Masjed Soleyman (مسجد سليمان) in southwest Persia, the first major commercial oil strike in the Middle East is made. The rights to the resource are quickly acquired by the Anglo-Persian Oil Company.
- 1917 – Several powerful tornadoes rip through Illinois, including the city of Mattoon, killing 101 people and injuring 689.
- 1918 – The Democratic Republic of Georgia is established.
- 1936 – In the House of Commons of Northern Ireland, Tommy Henderson begins speaking on the Appropriation Bill. By the time he sits down in the early hours of the following morning, he had spoken for 10 hours.
- 1938 – In the United States, the House Un-American Activities Committee begins its first session.
- 1940 – World War II: Battle of Dunkirk – In France, Allied forces begin a massive evacuation from Dunkirk, France.
- 1942 – World War II: The Battle of Bir Hakeim takes place.
- 1948 – The U.S. Congress passes Public Law 557, which permanently establishes the Civil Air Patrol as an auxiliary of the United States Air Force.
- 1966 – British Guiana gains independence, becoming Guyana.
- 1969 – Apollo program: Apollo 10 returns to Earth after a successful eight-day test of all the components needed for the forthcoming first manned moon landing.
- 1970 – The Soviet Tupolev Tu-144 becomes the first commercial transport to exceed Mach 2.
- 1972 – Willandra National Park is established in Australia.
- 1972 – The United States and the Soviet Union sign the Anti-Ballistic Missile Treaty.
- 1977 – George Willig climbs the South Tower of New York City's World Trade Center.
- 1981 – Prime Minister of Italy Arnaldo Forlani and his coalition cabinet resign following a scandal over membership of the pseudo-masonic lodge P2 (Propaganda Due).
- 1983 – A strong 7.7 magnitude earthquake strikes Japan, triggering a tsunami that kills at least 104 people and injures thousands. Many people go missing and thousands of buildings are destroyed.
- 1986 – The European Community adopts the European flag.
- 1991 – Zviad Gamsakhurdia becomes the first elected President of the Republic of Georgia in the post-Soviet era.
- 1991 – Lauda Air Flight 004 crashes in rural Thailand, killing 223.
- 1998 – The Supreme Court of the United States rules that Ellis Island, the historic gateway for millions of immigrants, is mainly in the state of New Jersey, not New York.
- 2004 – The United States Army veteran Terry Nichols is found guilty of 161 state murder charges for helping carry out the Oklahoma City bombing.
- 2011 – Ratko Mladić, Serbian war criminal, is arrested.
May 25
- 567 BC – Servius Tullius, king of Rome, celebrates a triumph for his victory over the Etruscans.
- 240 BC – First recorded perihelion passage of Halley's Comet.
- 1085 – Alfonso VI of Castile takes Toledo, Spain back from the Moors.
- 1420 – Henry the Navigator is appointed governor of the Order of Christ.
- 1521 – The Diet of Worms ends when Charles V, Holy Roman Emperor, issues the Edict of Worms, declaring Martin Luther an outlaw.
- 1659 – Richard Cromwell resigns as Lord Protector of England following the restoration of the Long Parliament, beginning a second brief period of the republican government called the Commonwealth of England.
- 1738 – A treaty between Pennsylvania and Maryland ends the Conojocular War with settlement of a boundary dispute and exchange of prisoners.
- 1798 – United Irishmen Rebellion: The Carnew massacre, Dunlavin massacre and Carlow massacre takes place.
- 1809 – Chuquisaca Revolution: a group of patriots in Chuquisaca (modern day Sucre) revolt against the Spanish Empire, starting the South American Wars of Independence.
- 1810 – May Revolution: citizens of Buenos Aires expel Viceroy Baltasar Hidalgo de Cisneros during the May week, starting the Argentine War of Independence.
- 1819 – The Argentine Constitution of 1819 is promulgated.
- 1833 – The Chilean Constitution of 1833 is promulgated.
- 1837 – The Rebels of Lower Canada (Quebec) rebel against the British for freedom.
- 1865 – In Mobile, Alabama, 300 are killed when an ordnance depot explodes.
- 1878 – Gilbert and Sullivan's comic opera H.M.S. Pinafore opens at the Opera Comique in London.
- 1895 – Playwright, poet, and novelist Oscar Wilde is convicted of "committing acts of gross indecency with other male persons" and sentenced to serve two years in prison.
- 1895 – The Republic of Formosa is formed, with Tang Ching-sung as its president.
- 1914 – The United Kingdom's House of Commons passes the Home Rule Act for devolution in Ireland.
- 1925 – Scopes Trial: John T. Scopes is indicted for teaching Charles Darwin's theory of evolution.
- 1926 – Sholom Schwartzbard assassinates Symon Petliura, the head of the Paris-based government-in-exile of Ukrainian People's Republic.
- 1935 – Jesse Owens of Ohio State University breaks three world records and ties a fourth at the Big Ten Conference Track and Field Championships in Ann Arbor, Michigan.
- 1936 – The Remington Rand strike, led by the American Federation of Labor, begins.
- 1938 – Spanish Civil War: The bombing of Alicante takes place, with 313 deaths.
- 1946 – The parliament of Transjordan makes Abdullah I of Jordan their Emir.
- 1953 – Nuclear testing: At the Nevada Test Site, the United States conduct their first and only nuclear artillery test.
- 1953 – The first public television station in the United States officially begins broadcasting as KUHT from the campus of the University of Houston.
- 1955 – In the United States, a night time F5 tornado strikes the small city of Udall, Kansas, killing 80 and injuring 273. It is the deadliest tornado to ever occur in the state and the 23rd deadliest in the U.S.
- 1955 – First ascent of Kangchenjunga (8,586 m.), the third highest mountain in the world, by a British expedition led by Joe Brown and George Band.
- 1961 – Apollo program: U.S. President John F. Kennedy announces before a special joint session of the Congress his goal to initiate a project to put a "man on the Moon" before the end of the decade.
- 1962 – The Old Bay Line, the last overnight steamboat service in the United States, goes out of business.
- 1963 – In Addis Ababa, Ethiopia, the Organisation of African Unity is established.
- 1966 – Explorer program: Explorer 32 launches.
- 1966 – The first prominent dàzìbào during the Cultural Revolution in China is posted at Peking University.
- 1967 – Celtic F.C. from Glasgow, Scotland becomes the first ever Northern European team to win the European Cup; with previous winners being from Spain, Italy and Portugal.
- 1973 – HNS Velos (D-16), while participating in a NATO exercise and in order to protest against the dictatorship in Greece, anchored at Fiumicino, Italy, refusing to return to Greece.
- 1977 – Star Wars (retitled Star Wars Episode IV: A New Hope in 1981) is released in theaters, inspiring the Jediism religion and Geek Pride Day holiday.
- 1979 – American Airlines Flight 191: In Chicago, a McDonnell Douglas DC-10 crashes during takeoff at O'Hare International Airport killing 271 on board and two people on the ground.
- 1979 – Six-year-old Etan Patz disappears from the street just two blocks away from his New York City home, prompting an international search for the child, and causing U.S. President Ronald Reagan to designate May 25th as National Missing Children's Day (in 1983).
- 1981 – In Riyadh, the Gulf Cooperation Council is created between Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates.
- 1982 – HMS Coventry is sunk during the Falklands War.
- 1985 – Bangladesh is hit by a tropical cyclone and storm surge, which kills approximately 10,000 people.
- 1997 – A military coup in Sierra Leone replaces President Ahmad Tejan Kabbah with Major Johnny Paul Koromah.
- 1999 – The United States House of Representatives releases the Cox Report which details the People's Republic of China's nuclear espionage against the U.S. over the prior two decades.
- 2000 – Liberation Day of Lebanon. Israel withdraws its army from most of the Lebanese territory after 22 years of its first invasion in 1978.
- 2001 – 32-year-old Erik Weihenmayer, of Boulder, Colorado, becomes the first blind person to reach the summit of Mount Everest.
- 2002 – China Airlines Flight 611: A Boeing 747-200 breaks apart in mid-air and plunges into the Taiwan Strait killing 225 people.
- 2002 – A train crash in Tenga, Mozambique kills 197 people.
- 2009 – North Korea allegedly tests its second nuclear device. Following the nuclear test, Pyongyang also conducted several missile tests building tensions in the international community.
- 2011 – Oprah Winfrey airs her last show, ending her twenty five year run of The Oprah Winfrey Show.
May 24
- 1218 – The Fifth Crusade leaves Acre for Egypt.
- 1276 – Magnus Ladulås is crowned King of Sweden in Uppsala Cathedral.
- 1487 – The ten-year-old Lambert Simnel is crowned in Christ Church Cathedral in Dublin, Ireland with the name of Edward VI in a bid to threaten King Henry VII's reign.
- 1595 – Nomenclator of Leiden University Library appears, the first printed catalog of an institutional library.
- 1621 – The Protestant Union is formally dissolved.
- 1626 – Peter Minuit buys Manhattan.
- 1689 – The English Parliament passes the Act of Toleration protecting Protestants. Roman Catholics are intentionally excluded.
- 1738 – John Wesley is converted, essentially launching the Methodist movement; the day is celebrated annually by Methodists as Aldersgate Day and a church service is generally held on the preceding Sunday.
- 1798 – The Irish Rebellion of 1798 led by the United Irishmen against British rule begins.
- 1822 – Battle of Pichincha: Antonio José de Sucre secures the independence of the Presidency of Quito.
- 1830 – Mary Had a Little Lamb by Sarah Josepha Hale is published.
- 1830 – The first revenue trains in the United States begin service on the Baltimore and Ohio Railroad between Baltimore, Maryland and Ellicott's Mills, Maryland.
- 1832 – The First Kingdom of Greece is declared in the London Conference.
- 1844 – Samuel Morse sends the message "What hath God wrought" (a biblical quotation, Numbers 23:23) from the Old Supreme Court Chamber in the United States Capitol to his assistant, Alfred Vail, in Baltimore, Maryland to inaugurate the first telegraph line.
- 1846 – Mexican-American War: General Zachary Taylor captures Monterrey.
- 1856 – John Brown and his men murder five slavery supporters at Pottawatomie Creek, Kansas.
- 1861 – American Civil War: Union troops occupy Alexandria, Virginia.
- 1883 – The Brooklyn Bridge in New York City is opened to traffic after 14 years of construction.
- 1895 – Henry Irving becomes the first person from the theatre to be knighted.
- 1900 – Second Boer War: The United Kingdom annexes the Orange Free State.
- 1901 – Seventy-eight miners die in the Caerphilly pit disaster in South Wales.
- 1915 – World War I: Italy declares war on Austria-Hungary.
- 1921 – The trial of Sacco and Vanzetti opens.
- 1930 – Amy Johnson lands in Darwin, Northern Territory, becoming the first woman to fly solo from England to Australia (she left on May 5 for the 11,000 mile flight).
- 1935 – The first night game in Major League Baseball history is played in Cincinnati, Ohio, with the Cincinnati Reds beating the Philadelphia Phillies 2-1 at Crosley Field.
- 1940 – Igor Sikorsky performs the first successful single-rotor helicopter flight.
- 1941 – World War II: In the Battle of the Atlantic, the German Battleship Bismarck sinks the then pride of the Royal Navy, HMS Hood, killing all but three crewmen.
- 1943 – Holocaust: Josef Mengele becomes chief medical officer of the Auschwitz concentration camp.
- 1948 – Arab–Israeli War: Egypt captures the Israeli kibbutz of Yad Mordechai, but the five-day effort gives Israeli forces time to prepare enough to stop the Egyptian advance a week later.
- 1956 – Conclusion of the Sixth Buddhist Council on Vesak Day, marking the 2,500 year anniversary after the Lord Buddha's Parinibbāna.
- 1956 – The first Eurovision Song Contest is held in Lugano, Switzerland
- 1958 – United Press International is formed through a merger of the United Press and the International News Service.
- 1960 – Following the 1960 Valdivia earthquake, the largest ever recorded earthquake, Cordón Caulle begins to erupt.
- 1961 – American civil rights movement: Freedom Riders are arrested in Jackson, Mississippi for "disturbing the peace" after disembarking from their bus.
- 1961 – Cyprus enters the Council of Europe.
- 1962 – Project Mercury: American astronaut Scott Carpenter orbits the Earth three times in the Aurora 7 space capsule.
- 1967 – Egypt imposes a blockade and siege of the Red Sea coast of Israel.
- 1968 – FLQ separatists bomb the U.S. consulate in Quebec City.
- 1970 – The drilling of the Kola Superdeep Borehole begins in the Soviet Union.
- 1973 – Earl Jellicoe resigns as Lord Privy Seal and Leader of the House of Lords.
- 1976 – The London to Washington, D.C. Concorde service begins.
- 1976 – The Judgement of Paris takes place in France, launching California as a worldwide force in the production of quality wine.
- 1980 – The International Court of Justice calls for the release of United States embassy hostages in Tehran, Iran. The hostages would not be freed until the following January.
- 1982 – Liberation of Khorramshahr: Iranians recapture of the port city of Khorramshahr from the Iraqis during the Iran–Iraq War.
- 1988 – Section 28 of the United Kingdom's Local Government Act 1988, a controversial amendment stating that a local authority cannot intentionally promote homosexuality, is enacted.
- 1989 – Sonia Sutcliffe, wife of the Yorkshire Ripper Peter Sutcliffe, is awarded £600,000 in damages (later reduced to £60,000 on appeal) after winning a libel action against Private Eye.
- 1990 – A car carrying American Earth First! activists Judi Bari and Darryl Cherney explodes in Oakland, California, critically injuring both.
- 1991 – Eritrea gains its independence from Ethiopia.
- 1991 – Israel conducts Operation Solomon, evacuating Ethiopian Jews to Israel.
- 1992 – The last Thai dictator, General Suchinda Kraprayoon, resigns following pro-democracy protests.
- 1994 – Four men convicted of bombing the World Trade Center in New York in 1993 are each sentenced to 240 years in prison.
- 2000 – Israeli troops withdraw from southern Lebanon after 22 years of occupation.
- 2001 – Mountain climbing: 15-year-old Sherpa Temba Tsheri becomes the youngest person to climb to the top of Mount Everest.
- 2001 – The Versailles wedding hall disaster in Jerusalem, Israel, kills 23 and injures over 200
- 2002 – Russia and the United States sign the Moscow Treaty.
- 2004 – Communications in North Korea: North Korea bans mobile phones.