1122 – Pope Callixtus II and Holy Roman Emperor Henry V agree to the Concordat of Worms to put an end to the Investiture Controversy.
1338 – The Battle of Arnemuiden was the first naval battle of the Hundred Years’ War and the first naval battle using artillery, as the English ship Christopher had three cannons and one hand gun.
1409 – Battle of Kherlen, the second significant victory over Ming dynasty China by the Mongols since 1368.
1459 – Battle of Blore Heath, the first major battle of the English Wars of the Roses, takes place.
1568 – Spanish naval forces rout an English fleet, under the command of John Hawkins, at the Battle of San Juan de Ulúa near Veracruz.
1641 – The Merchant Royal, carrying a treasure of over 100,000 pounds of gold (worth over £1 billion today), is lost at sea off Land’s End.
1642 – First commencement exercises occur at Harvard College.
1779 – American Revolution: John Paul Jones on board the USS Bonhomme Richard wins the Battle of Flamborough Head.
1780 – American Revolution: British Major John André is arrested as a spy by American soldiers exposing Benedict Arnold’s change of sides.
1803 – Second Anglo-Maratha War: Battle of Assaye between the British East India Company and the Maratha Empire in India.
1806 – Lewis and Clark return to St. Louis after exploring the Pacific Northwest of the United States.
1821 – Tripolitsa, Greece, is captured by Greek rebels during the Greek War of Independence.
1845 – The Knickerbockers Baseball Club, the first baseball team to play under the modern rules, is founded in New York.
1846 – Astronomers Urbain Jean Joseph Le Verrier, John Couch Adams and Johann Gottfried Galle collaborate on the discovery of Neptune.
1868 – Grito de Lares (“Lares Revolt”) occurs in Puerto Rico against Spanish rule.
1889 – Nintendo Koppai (Later Nintendo Company, Limited) is founded by Fusajiro Yamauchi to produce and market the playing card game Hanafuda.
1899 – American Asiatic Squadron destroys a Filipino battery at the Battle of Olongapo.
1905 – Norway and Sweden sign the “Karlstad treaty”, peacefully dissolving the Union between the two countries.
1909 – The Phantom of the Opera (original title: Le Fantôme de l’Opéra), a novel by French writer Gaston Leroux, is first published as a serialization in Le Gaulois.
1911 – Pilot Earle Ovington makes the first official airmail delivery in America under the authority of the United States Post Office Department
1913 – Roland Garros of France becomes the first to fly in an airplane across the Mediterranean (from St. Raphael France to Bizerte, Tunisia).
1932 – The Kingdom of Hejaz and Nejd is renamed the Kingdom of Saudi Arabia.
1938 – Mobilization of the Czechoslovak army in response to the Munich Agreement.
1942 – World War II: The Matanikau action on Guadalcanal begins: U.S. Marines attack Japanese units along the Matanikau River.
1943 – World War II: The Nazi puppet state known as the Italian Social Republic is founded.
1950 – Korean War: The Battle of Hill 282: The first US friendly-fire incident on British military personnel since World War II occurs.
1962 – The Lincoln Center for the Performing Arts opens in New York City.
1973 – Argentine general election: Juan Perón returns to power in Argentina.
1980 – Bob Marley plays what would be his last concert in Pittsburgh.
1983 – Saint Kitts and Nevis joins the United Nations.
1983 – Gulf Air Flight 771 is destroyed by a bomb, killing all 117 people on board.
1986 – Jim Deshaies of the Houston Astros sets a major league record by striking out the first eight batters he faces in a game against the Los Angeles Dodgers.
2002 – The first public version of the web browser Mozilla Firefox (“Phoenix 0.1”) is released.
2004 – Over 3,000 people die in Haiti after Hurricane Jeanne produces massive flooding and mudslides.
2008 – Kauhajoki school shooting: Matti Saari kills ten people before committing suicide.