June 24 is the 175th day of the year (176th in leap years) in the Gregorian calendar; 190 days remain until the end of the year.
1312 BC – Mursili II launches a campaign against the Kingdom of Azzi-Hayasa.
217 BC – The Romans, led by Gaius Flaminius, are ambushed and defeated by Hannibal at the Battle of Lake Trasimene.
109 – Roman emperor Trajan inaugurates the Aqua Traiana, an aqueduct that channels water from Lake Bracciano, 40 kilometres (25 miles) northwest of Rome.
474 – Julius Nepos forces Roman usurper Glycerius to abdicate the throne and proclaims himself Emperor of the Western Roman Empire.
637 – The Battle of Moira is fought between the High King of Ireland and the Kings of Ulster and Dál Riata. It is claimed to be the largest battle in the history of Ireland.
843 – The Vikings sack French city of Nantes.
972 – Battle of Cedynia, the first documented victory of Polish forces, takes place.
1128 – Battle of São Mamede, near Guimarães: Forces led by Afonso I defeat forces led by his mother Teresa of León and her lover Fernando Pérez de Traba.
1230 – The Siege of Jaén begins, in the context of the Spanish Reconquista.
1314 – First War of Scottish Independence: The Battle of Bannockburn concludes with a decisive victory by Scottish forces led by Robert the Bruce.
1340 – Hundred Years' War: Battle of Sluys: The French fleet is almost completely destroyed by the English fleet commanded in person by King Edward III.
1374 – A sudden outbreak of St. John's Dance causes people in the streets of Aachen, Germany, to experience hallucinations and begin to jump and twitch uncontrollably until they collapse from exhaustion.
1497 – John Cabot lands in North America at Newfoundland leading the first European exploration of the region since the Vikings.
1509 – Henry VIII and Catherine of Aragon are crowned King and Queen of England.
1535 – The Anabaptist state of Münster is conquered and disbanded.
1540 – English King Henry VIII commands his fourth wife, Anne of Cleves, to leave the court.
1571 – Miguel López de Legazpi founds Manila, the capital of the Philippines.
1593 – The Dutch city of Geertruidenberg held by the Spanish, capitulates to a besieging Dutch and English army led by Maurice of Nassau.
1604 – Samuel de Champlain discovers the mouth of the Saint John River, site of Reversing Falls and the present-day city of Saint John, New Brunswick, Canada.
1622 – Battle of Macau: The Dutch make a failed attempt to capture Macau.
1663 – The Spanish garrison of Évora capitulates, following the Portuguese victory at the Battle of Ameixial.
1717 – The Premier Grand Lodge of England is founded in London, the first Masonic Grand Lodge in the world (now the United Grand Lodge of England).
1762 – Battle of Wilhelmsthal: The British-Hanoverian army of Ferdinand of Brunswick defeats French forces in Westphalia.
1779 – American Revolutionary War: The Great Siege of Gibraltar begins.
1793 – The first Republican constitution in France is adopted.
1812 – Napoleonic Wars: Napoleon's Grande Armée crosses the Neman river beginning the invasion of Russia.
1813 – Battle of Beaver Dams: A British and Indian combined force defeats the United States Army.
1821 – Battle of Carabobo: Decisive battle in the war of independence of Venezuela from Spain.
1859 – Battle of Solferino (Battle of the Three Sovereigns): Sardinia and France defeat Austria in Solferino, northern Italy.
1866 – Battle of Custoza: An Austrian army defeats the Italian army during the Austro-Prussian War.
1880 – First performance of O Canada at the Congrès national des Canadiens-Français. The song would later become the national anthem of Canada.
1894 – Marie François Sadi Carnot is assassinated by Sante Geronimo Caserio.
1913 – Greece and Serbia annul their alliance with Bulgaria.
1916 – Mary Pickford becomes the first female film star to sign a million-dollar contract.
1918 – First airmail service in Canada from Montreal to Toronto.
1922 – The American Professional Football Association is renamed the National Football League.
1932 – A bloodless revolution instigated by the People's Party ends the absolute power of King Prajadhipok of Siam (now Thailand).
1938 – Pieces of a meteorite land near Chicora, Pennsylvania. The meteorite is estimated to have weighed 450 metric tons when it hit the Earth's atmosphere and exploded.
1939 – Siam is renamed Thailand by Plaek Phibunsongkhram, the country's third prime minister.
1940 – World War II: Operation Collar, the first British Commando raid on occupied France, by No 11 Independent Company.
1943 – US military police attempt to arrest a black soldier in Bamber Bridge, England, sparking the Battle of Bamber Bridge mutiny that leaves one dead and seven wounded.
1947 – Kenneth Arnold makes the first widely reported UFO sighting near Mount Rainier, Washington.
1948 – Cold War: Start of the Berlin Blockade: The Soviet Union makes overland travel between West Germany and West Berlin impossible.
1949 – The first television western, Hopalong Cassidy, starring William Boyd, is aired on NBC.
1950 – Apartheid: In South Africa, the Group Areas Act is passed, formally segregating races.
1954 – First Indochina War: Battle of Mang Yang Pass: Viet Minh troops belonging to the 803rd Regiment ambush G.M. 100 of France in An Khê.
1957 – In Roth v. United States, the U.S. Supreme Court rules that obscenity is not protected by the First Amendment.
1960 – Assassination attempt of Venezuelan President Rómulo Betancourt.
1963 – The United Kingdom grants Zanzibar internal self-government.
1973 – The UpStairs Lounge arson attack takes place at a gay bar located on the second floor of the three-story building at 141 Chartres Street in the French Quarter of New Orleans, Louisiana, USA. Thirty-two people die as a result of fire or smoke inhalation.
1975 – Eastern Air Lines Flight 66 encounters severe wind shear and crashes on final approach to New York's JFK Airport killing 113 of the 124 passengers on board, making it the deadliest U.S. plane crash at the time. This accident led to decades of research into downburst and microburst phenomena and their effects on aircraft.
1981 – The Humber Bridge opens to traffic, connecting Yorkshire and Lincolnshire. It remained the world's longest bridge span for 17 years.
1982 – "The Jakarta Incident": British Airways Flight 9 flies into a cloud of volcanic ash thrown up by the eruption of Mount Galunggung, resulting in the failure of all four engines.
1989 – Jiang Zemin succeeds Zhao Ziyang to become the General Secretary of the Chinese Communist Party after the 1989 Tiananmen Square protests and massacre.
1995 – Rugby World Cup: South Africa defeats New Zealand and Nelson Mandela presents Francois Pienaar with the Webb Ellis Cup in an iconic post-apartheid moment.
2002 – The Igandu train disaster in Tanzania kills 281, the worst train accident in African history.
2004 – In New York, capital punishment is declared unconstitutional.
2010 – At Wimbledon, John Isner of the United States defeats Nicolas Mahut of France, in the longest match in professional tennis history.
2010 – Julia Gillard assumes office as the first female Prime Minister of Australia.
2012 – Death of Lonesome George, the last known individual of Chelonoidis nigra abingdonii, a subspecies of the Galápagos tortoise.
2013 – Former Italian Prime Minister Silvio Berlusconi is found guilty of abusing his power and engaging in sex with an underage prostitute, and is sentenced to seven years in prison.
2021 – The Champlain Towers South condominium in Surfside, Florida suffers a sudden partial collapse, killing 98 people inside.
Holidays and observances
Army Day or Battle of Carabobo Day (Venezuela)
Bannockburn Day (Scotland)
Christian feast day:
María Guadalupe García Zavala
Nativity of Saint John the Baptist
June 24 (Eastern Orthodox liturgics)
Day of the Caboclo (Amazonas, Brazil)
Inti Raymi, a winter solstice festival and a New Year in the Andes of the Southern Hemisphere (Sacsayhuamán)
St John's Day and the second day of the Midsummer celebrations (although this is not the astronomical summer solstice, see June 20) (Roman Catholic Church, Europe), and its related observances:
Midsummer Day (England)
Saint Jonas' Festival or Joninės (Lithuania)
Saint-Jean-Baptiste Day (Quebec)
Sânziene (western Carpathian Mountains of Romania)
Wattah Wattah Festival (Philippines)
Fors Fortuna, ancient Roman festival to Fortuna