October 9 is the 282nd day of the year (283rd in leap years) in the Gregorian calendar; 83 days remain until the end of the year.
1604 – Kepler's Supernova is the most recent supernova to be observed within the Milky Way.
1635 – Roger Williams is banished from the Massachusetts Bay Colony after religious and policy disagreements.
1701 – The Collegiate School of Connecticut (later renamed Yale University) is chartered in Old Saybrook.
1708 – Peter the Great defeats the Swedes at the Battle of Lesnaya.
1740 – Dutch colonists and Javanese natives begin a massacre of the ethnic Chinese population in Batavia, eventually killing at least 10,000.
1760 – Seven Years' War: Russian and Austrian troops briefly occupy Berlin.
1790 – A severe earthquake in northern Algeria causes severe damage and a tsunami in the Mediterranean Sea and kills 3,000.
1799 – HMS Lutine sinks with the loss of 240 men and a cargo worth 1.2 million pounds British currency.
1812 – War of 1812: In a naval engagement on Lake Erie, American forces capture two British ships: HMS Detroit and HMS Caledonia.
1825 – Restauration arrives in New York Harbor from Norway, the first organized immigration from Norway to the United States.
1834 – Opening of the Dublin and Kingstown Railway, the first public railway on the island of Ireland.
1847 – Slavery is abolished in the Swedish colony of Saint Barthélemy.
1861 – American Civil War: Union troops repel a Confederate attempt to capture Fort Pickens at the Battle of Santa Rosa Island.
1864 – American Civil War: Union cavalrymen defeat Confederate forces at Toms Brook, Virginia.
1873 – A meeting at the U.S. Naval Academy establishes the U.S. Naval Institute.
1911 – An accidental bomb explosion triggers the Wuchang Uprising against the Qing dynasty, beginning the Xinhai Revolution.
1913 – The steamship SS Volturno catches fire in the mid-Atlantic.
1914 – World War I: The Siege of Antwerp comes to an end.
1918 – The Finnish Parliament offers to Prince Frederick Charles of Hesse the throne of a short-lived Kingdom of Finland.
1919 – The Cincinnati Reds win the World Series, resulting in the Black Sox Scandal.
1934 – An Ustashe assassin kills King Alexander I of Yugoslavia and Louis Barthou, Foreign Minister of France, in Marseille.
1936 – Boulder Dam (later Hoover Dam) begins to generate electricity and transmit it to Los Angeles.
1937 – Murder of 9 Catholic priests in Zhengding, China, who protected the local population from the advancing Japanese army.
1941 – A coup in Panama declares Ricardo Adolfo de la Guardia Arango the new president.
1942 – Australia's Statute of Westminster Adoption Act 1942 receives royal assent.
1950 – The Goyang Geumjeong Cave massacre in Korea begins.
1962 – Uganda becomes an independent Commonwealth realm.
1963 – In Italy, a large landslide causes a giant wave to overtop the Vajont Dam, killing over 2,000.
1966 – Vietnam War: the Republic of Korea Army commits the Binh Tai Massacre.
1967 – A day after his capture, Ernesto 'Che' Guevara is executed for attempting to incite a revolution in Bolivia.
1969 – In Chicago, the National Guard is called in as demonstrations continue over the trial of the 'Chicago Eight'.
1970 – The Khmer Republic is proclaimed in Cambodia.
1980 – Pope John Paul II greets the Dalai Lama during a private audience in Vatican City.
1981 – President François Mitterrand abolishes capital punishment in France.
1983 – South Korean President Chun Doohwan survives an assassination attempt in Rangoon, Burma (present- day Yangon, Myanmar), but the blast kills 21 and injures 17 others.
1984 – The popular children's television show Thomas The Tank Engine & Friends, based on The Railway Series by the Reverend Wilbert Awdry, premieres.
1986 – The Phantom of the Opera, eventually the second longest running musical in London, opens at Her Majesty's Theatre.
1986 – Fox Broadcasting Company (FBC) launches as the fourth US television network.
1992 – The Peekskill meteorite, a 27.7 pounds meteorite crashed into a parked car in Peekskill, New York 1995 – An Amtrak Sunset Limited train is derailed by saboteurs near Palo Verde, Arizona.