Editing October 20 (section)

===1901–present===
*[[1904]] &ndash; Chile and Bolivia sign the [[Treaty of Peace and Friendship (1904)|Treaty of Peace and Friendship]], delimiting the border between the two countries.
*[[1910]] &ndash; British [[ocean liner]] [[RMS Olympic|RMS ''Olympic'']] is launched.<ref>{{cite book |last=Piouffre |first=Gérard |year=2009 |title=Le Titanic ne répond plus |publisher=Larousse |language=fr |isbn=978-2-263-02799-4 |page=52}}</ref>
*[[1935]] &ndash; The [[Long March]], a mammoth retreat undertaken by the [[People's Liberation Army|armed forces]] of the [[Chinese Communist Party]] a year prior, ends.
*[[1941]] &ndash; [[World War II]]: Thousands of civilians in [[Territory of the Military Commander in Serbia|German-occupied Serbia]] are murdered in the [[Kragujevac massacre]].
*[[1944]] &ndash; World War II: The Soviet [[Red Army]] and [[Yugoslav Partisans]] [[Belgrade Offensive|liberate Belgrade]].
*  1944   &ndash; [[Liquefied natural gas]] leaks from storage tanks in Cleveland and then [[Cleveland East Ohio Gas explosion|explodes]], leveling 30 blocks and killing 130 people.
*  1944   &ndash; American general [[Douglas MacArthur]] fulfills his promise to return to the Philippines when he comes ashore during the [[Battle of Leyte]].
*[[1947]] &ndash; [[Cold War]]: The [[House Un-American Activities Committee]] begins its investigation into Communist infiltration of the [[Cinema of the United States|Hollywood film industry]], resulting in [[Hollywood blacklist|a blacklist]] that prevents some from working in the industry for years.
*[[1948]] &ndash; A [[KLM]] [[Lockheed L-049 Constellation]] [[1948 KLM Constellation air disaster|crashes]] on approach to [[Glasgow Prestwick Airport]], killing 40.<ref name="lyons">{{cite web |author=Lyons |first=Gordon |title=Constellation PH-TEN |url=http://www.aircrashsites-scotland.co.uk/constellation_mauchline.htm |access-date=31 May 2009 |publisher=Air Crash Sites Scotland}}</ref>
*[[1951]] &ndash; The "[[Johnny Bright incident]]" occurs during a football game between the [[Drake Bulldogs football|Drake Bulldogs]] and [[Oklahoma State Cowboys football|Oklahoma A&M Aggies]].
*[[1952]] &ndash; The Governor of Kenya [[Evelyn Baring, 1st Baron Howick of Glendale|Evelyn Baring]] declares a state of emergency and begins arresting hundreds of suspected leaders of the [[Mau Mau Uprising]].
*[[1961]] &ndash; The [[Soviet Navy]] performs the first armed test of a [[submarine-launched ballistic missile]], launching an [[R-13 (missile)|R-13]] from a [[Golf-class submarine]].
*[[1962]] &ndash; [[China]] launches simultaneous offensives in [[Ladakh]] and across the [[McMahon Line]], igniting the [[Sino-Indian War]].
*[[1973]] &ndash; [[Watergate scandal]]: "[[Saturday Night Massacre]]": United States President [[Richard Nixon]] fires U.S. Attorney General [[Elliot Richardson]] and Deputy Attorney General [[William Ruckelshaus]] after they refuse to fire special prosecutor [[Archibald Cox]], who is finally fired by Solicitor General [[Robert Bork]].
*  1973   &ndash; The [[Sydney Opera House]] is opened by [[Elizabeth II]] after 14 years of construction.
*[[1976]] &ndash; The [[Luling–Destrehan Ferry]] [[MV George Prince ferry disaster|MV ''George Prince'' is struck]] by the Norwegian freighter [[SS Frosta|SS ''Frosta'']] while crossing the [[Mississippi River]] in [[St. Charles Parish, Louisiana]]. Seventy-eight passengers and crew die, and only 18 people aboard the ferry survive.
*[[1977]] &ndash; A plane carrying the rock band [[Lynyrd Skynyrd]] [[Lynyrd Skynyrd plane crash|crashes]] in woodland in [[Mississippi]], United States. Six people, including three band members, are killed.<ref>{{cite web | url=https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR7806.pdf |title=Aircraft Accident Report – L & J Company, Convair 248, N55VM, Gillsburg, Mississippi, October 20, 1977 |date=June 19, 1978 |publisher=U.S. National Transportation Safety Board}}</ref>
*[[1981]] &ndash; Two police officers and a [[Brink's]] armored car guard are killed during an [[Brink's robbery (1981)|armed robbery]] carried out by members of the [[Black Liberation Army]] and [[Weather Underground]] in [[Nanuet, New York]]. 
*[[1982]] &ndash; During the UEFA Cup match between [[FC Spartak Moscow]] and [[HFC Haarlem]], 66 people are crushed to death in the [[Luzhniki disaster]].
*[[1986]] &ndash; [[Aeroflot Flight 6502]] crashes while landing at Kuibyshev Airport (now [[Kurumoch International Airport|Kuromoch International Airport]]) in Kuibyshev (now present-day [[Samara]], [[Russia]]), killing 70 people.<ref name="ASN">{{Cite web|last=Ranter|first=Harro|title=ASN Aircraft accident Tupolev Tu-134A CCCP-65766 Kuybyshev Airport (KUF)|url=https://aviation-safety.net/database/record.php?id=19861020-1|access-date=2020-09-23|website=aviation-safety.net|publisher=[[Aviation Safety Network]]}}</ref>
*[[1991]] &ndash; A 6.8 [[Moment magnitude scale|M<sub>w</sub>]] earthquake [[1991 Uttarkashi earthquake|strikes]] the [[Uttarkashi district|Uttarkashi]] region of India, killing more than 1,000 people.
*  1991   &ndash; A massive [[firestorm]] breaks out [[Oakland firestorm of 1991|in the hills of Oakland and Berkeley, California]] killing 25 people and destroying more than 3,000 homes, apartments and condominiums.<ref>{{cite web|url=https://abc7news.com/oakland-hills-fire-east-bay-1991-department/11141174/|title=Oakland Hills Fire 30 years later: Survivors' stories captured in new ABC7 documentary 'Firestorm'|date=20 October 2021|access-date=20 October 2021|work=[[KGO-TV ABC San Francisco]]}}</ref>
*  [[1995]] &ndash; [[Space Shuttle Columbia|Space Shuttle ''Columbia'']] launches on [[STS-73]].<ref>{{cite web |title=Mission Archives |url=http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-73.html |access-date=16 August 2010 |website=NASA}}</ref>
*[[2002]] &ndash; ''[[Top Gear (2002 TV series)|Top Gear]]'', the revived popular British TV motoring magazine, premieres on [[BBC]].<ref>{{Cite news|url = http://news.bbc.co.uk/1/hi/entertainment/5367516.stm|title=BBC News article on ''Top Gear's'' history|date=21 September 2006}}</ref>
*[[2003]] &ndash; The [[Sloan Great Wall]], once the [[List of largest cosmic structures|largest cosmic structures known to humanity]], is discovered by students at [[Princeton University]].<ref>{{Cite journal|last1=Gott III|first1=J. Richard|last2=Jurić|first2=Mario|last3=Schlegel|first3=David|last4=Hoyle|first4=Fiona|last5=Vogeley|first5=Michael|last6=Tegmark|first6=Max|last7=Bahcall|first7=Neta|last8=Brinkmann|first8=Jon|date=2005-05-10|title=A Map of the Universe|journal=The Astrophysical Journal|volume=624|issue=2|pages=463–484|doi=10.1086/428890|arxiv=astro-ph/0310571 |bibcode=2005ApJ...624..463G |s2cid=9654355 |issn=0004-637X}}</ref>
*[[2005]] &ndash; The general conference of the [[United Nations Educational, Scientific and Cultural Organization]] (UNESCO) passes the [[Convention on the Protection and Promotion of the Diversity of Cultural Expressions]].<ref>{{cite book |editor1-last=Beukelaer |editor1-first=Christiaan |editor2-last=Pyykkönen |editor2-first=Miikka |editor3-last=Singh |editor3-first=J. P. |title=Globalization, culture and development : the UNESCO Convention on Cultural Diversity |date=2015 |publisher=Palgrave Macmillan |location=Houndmills, Basingstoke, Hampshire |isbn=978-1-137-39763-8|page=1|chapter=Introduction: UNESCO's "Diversity Convention" – Ten Years on|author1-first=Christiaan |author1-last=De Beukelaer |author2-first= Miikka |author2-last=Pyykkönen}}</ref>
*[[2011]] &ndash; [[Libyan Crisis (2011–present)|Libyan Crisis]]: Rebel forces capture Libyan dictator [[Muammar Gaddafi]] and his son [[Mutassim Gaddafi|Mutassim]] in his hometown of Sirte and [[Death of Muammar Gaddafi|kill him]] shortly thereafter, ending the [[first Libyan civil war]].
*[[2017]] &ndash; [[Syrian civil war]]: The [[Syrian Democratic Forces]] (SDF) declare victory in the [[Raqqa campaign (2016–2017)|Raqqa campaign]].<ref>{{cite web|url=https://abcnews.go.com/International/us-backed-syrian-force-declares-victory-isis-capital/story?id=50605976|title=US-backed Syrian forces declare victory over ISIS in its former 'capital,' Raqqa|author1=Luis Martinez|author2=Morgan Winsor|date=20 October 2017|access-date=20 October 2017|publisher=ABC News|location=United States}}</ref>
*[[2022]] &ndash; [[Liz Truss]] steps down as [[British prime minister|British Prime Minister]] and leader of the [[Conservative Party (UK)|Conservative Party]] amid the country's political crisis, serving for the least time of any British Prime Minister [49 days].<ref>{{Cite news |date=2022-10-20 |title=Liz Truss resigns: PM's exit kicks off another Tory leadership race |language=en-GB |publisher=BBC News |url=https://www.bbc.com/news/uk-politics-63332037 |access-date=2022-10-24}}</ref>