| 122341 | October 26 | Event | 1917 – World War I: Brazil declares war on the Central Powers. |
| 122342 | October 26 | Event | 1918 – Erich Ludendorff, quartermaster-general of the Imperial German Army, is dismissed by Kaiser Wilhelm II of Germany for refusing to cooperate in peace negotiations. |
| 122343 | October 26 | Event | 1921 – The Chicago Theatre opens. |
| 122344 | October 26 | Event | 1936 – The first electric generator at Hoover Dam goes into full operation. |
| 122345 | October 26 | Event | 1940 – The P-51 Mustang makes its maiden flight. |
| 122346 | October 26 | Event | 1942 – World War II: In the Battle of the Santa Cruz Islands during the Guadalcanal Campaign, one U.S. aircraft carrier, Hornet, is sunk and another aircraft carrier, Enterprise, is heavily damaged, while two Japanese carriers and one cruiser are heavily |
| 122347 | October 26 | Event | 1943 – World War II: First flight of the Dornier Do 335 "Pfeil". |
| 122348 | October 26 | Event | 1944 – World War II: The Battle of Leyte Gulf ends with an overwhelming American victory. |
| 122349 | October 26 | Event | 1947 – The Maharaja of Kashmir and Jammu agrees to allow his kingdom to join India. |
| 122350 | October 26 | Event | 1955 – After the last Allied troops have left the country and following the provisions of the Austrian Independence Treaty, Austria declares permanent neutrality. |
| 122351 | October 26 | Event | 1955 – Ngô Đình Diệm declares himself Premier of South Vietnam. |
| 122352 | October 26 | Event | 1958 – Pan American Airways makes the first commercial flight of the Boeing 707 from New York City to Paris, France. |
| 122353 | October 26 | Event | 1964 – Eric Edgar Cooke becomes last person in Western Australia to be executed. |
| 122354 | October 26 | Event | 1967 – Mohammad Reza Pahlavi crowns himself Emperor of Iran and then crowns his wife Farah Empress of Iran. |
| 122355 | October 26 | Event | 1968 – Soviet cosmonaut Georgy Beregovoy pilots Soyuz 3 into space for a four-day mission. |
| 122356 | October 26 | Event | 1970 – Muhammad Ali faces off against Jerry Quarry in Atlanta, Georgia for the first time after Ali's three-year hiatus from evading to be drafted in the Vietnam War. |
| 122357 | October 26 | Event | 1977 – Ali Maow Maalin, the last natural case of smallpox, develops rash in Merca district, Somalia. The World Health Organization and the Centers for Disease Control and Prevention consider this date the anniversary of the eradication of smallpox, the mo |
| 122358 | October 26 | Event | 1979 – Park Chung-hee, President of South Korea is assassinated by Korean Central Intelligence Agency head Kim Jae-gyu. Choi Kyu-hah becomes the acting President Kim is executed the following May. |
| 122359 | October 26 | Event | 1984 – "Baby Fae" receives a heart transplant from a baboon. |
| 122360 | October 26 | Event | 1985 – The Australian government returns ownership of Uluru to the local Pitjantjatjara Aborigines. |
| 122361 | October 26 | Event | 1988 – Ronald Reagan decides to tear down the new U.S. Embassy in Moscow because of Soviet listening devices in the building structure.[1] |
| 122362 | October 26 | Event | 1991 – History of Slovenia: Three months after the end of the Ten-Day War, the last soldier of the Yugoslav People's Army leaves the territory of the Republic of Slovenia. |
| 122363 | October 26 | Event | 1992 – The Charlottetown Accord fails to win majority support in a Canada wide referendum. |
| 122364 | October 26 | Event | 1992 – The London Ambulance Service is thrown into chaos after the implementation of a new CAD, or Computer Aided Dispatch, system which failed. |
| 122365 | October 26 | Event | 1994 – Jordan and Israel sign a peace treaty. |
| 122366 | October 26 | Event | 1995 – Israeli–Palestinian conflict: Mossad agents assassinate Islamic Jihad leader Fathi Shaqaqi in his hotel in Malta. |
| 122367 | October 26 | Event | 1999 – Britain's House of Lords votes to end the right of hereditary peers to vote in Britain's upper chamber of Parliament. |
| 122368 | October 26 | Event | 2000 – Laurent Gbagbo takes over as president of Côte d'Ivoire following a popular uprising against President Robert Guéï. |
| 122369 | October 26 | Event | 2001 – The United States passes the USA PATRIOT Act into law. |
| 122370 | October 26 | Event | 2002 – Moscow theater hostage crisis: Approximately 50 Chechen terrorists and 150 hostages die when Russian Spetsnaz storm a theater building in Moscow, which had been occupied by the terrorists during a musical performance three days before. |