October 27 is the 300th day of the year (301st in leap years) in the Gregorian calendar; 65 days remain until the end of the year.

• 312 – Constantine the Great is said to have received his famous Vision of the Cross.
• 1275 – Traditional founding of the city of Amsterdam.
• 1524 – French troops lay siege to Pavia.
• 1553 – Condemned as a heretic, Michael Servetus is burned at the stake just outside Geneva.

• 1644 – Second Battle of Newbury in the English Civil War.
• 1674 – The French garrison in Grave surrenders the town to a Dutch army after a difficult siege.^[1]
• 1682 – Philadelphia is founded in the Commonwealth of Pennsylvania.
• 1775 – King George III expands on his Proclamation of Rebellion in the Thirteen Colonies in his speech from the throne at the opening of Parliament.^[2]
• 1795 – The United States and Spain sign the Treaty of Madrid, which establishes the boundaries between Spanish colonies and the U.S.
• 1806 – The French Army under Napoleon enters Berlin following the Prussian defeat at the Battle of Jena–Auerstedt.
• 1810 – United States annexes the former Spanish colony of West Florida.
• 1838 – Missouri governor Lilburn Boggs issues the Extermination Order, which orders all Mormons to leave the state or be killed.
• 1863 – American Civil War: Union forces led by General William F. Smith defeat Confederate forces in the Battle of Brown's Ferry, opening up a supply line to the besieged city of Chattanooga, Tennessee.^[3]
• 1870 – Franco-Prussian War: Marshal Bazaine surrenders to Prussian forces at the conclusion of the Siege of Metz along with 140,000 French soldiers.

• 1907 – Fifteen people are killed in Hungary when gendarmes opened fire on a crowd gathered at a church consecration.
• 1914 – World War I: The new British battleship HMS Audacious is sunk by a minefield laid by the armed German merchant-cruiser Berlin.
• 1916 – Negus Mikael, marching on the Ethiopian capital in support of his son Emperor Iyasu V, is defeated by Fitawrari abte Giyorgis, securing the throne for Empress Zewditu I.
• 1919 – The Fourth Regional Congress of Peasants, Workers and Insurgents is held by the Makhnovshchina at Oleksandrivsk.^[4]
• 1922 – A referendum in Rhodesia rejects the country's annexation to the South African Union.
• 1924 – The Uzbek SSR is founded in the Soviet Union.
• 1930 – Ratifications exchanged in London for the first London Naval Treaty go into effect immediately, further limiting the expensive naval arms race among its five signatories.
• 1936 – Mrs. Wallis Simpson obtains her divorce, which would eventually allow her to marry King Edward VIII of the United Kingdom, thus forcing his abdication from the throne.^[5]
• 1944 – World War II: German forces capture Banská Bystrica during Slovak National Uprising thus bringing it to an end.
• 1948 – Ecological disaster in Donora, Pennsylvania.^[6]
• 1954 – Benjamin O. Davis, Jr. becomes the first African-American general in the United States Air Force.
• 1958 – Iskander Mirza, the first President of Pakistan, is deposed by General Ayub Khan, who had been appointed the enforcer of martial law by Mirza 20 days earlier.
• 1961 – NASA tests the first Saturn I rocket in Mission Saturn-Apollo 1.
• 1962 – Major Rudolf Anderson of the United States Air Force becomes the only direct human casualty of the Cuban Missile Crisis when his U-2 reconnaissance airplane is shot down over Cuba by a Soviet-supplied surface-to-air missile.
• 1962 – By refusing to agree to the firing of a nuclear torpedo at a US warship, Vasily Arkhipov averts nuclear war.
• 1964 – Ronald Reagan delivers a speech on behalf of the Republican candidate for president, Barry Goldwater. The speech launches his political career and comes to be known as "A Time for Choosing".
• 1971 – The Democratic Republic of the Congo is renamed Zaire.
• 1979 – Saint Vincent and the Grenadines gains its independence from the United Kingdom.
• 1981 – Cold War: The Soviet submarine S-363 runs aground on the east coast of Sweden.
• 1986 – The British government suddenly deregulates financial markets, leading to a total restructuring of the way in which they operate in the country, in an event now referred to as the Big Bang.
• 1988 – Cold War: Ronald Reagan suspends construction of the new U.S. Embassy in Moscow due to Soviet listening devices in the building structure.
• 1991 – Turkmenistan achieves independence from the Soviet Union.
• 1992 – United States Navy radioman Allen R. Schindler, Jr. is murdered by shipmate Terry M. Helvey for being gay, precipitating debate about gays in the military that results in the United States' "Don't ask, don't tell" military policy.
• 1993 – Widerøe Flight 744 crashes in Overhalla Municipality, Norway, killing six people.^[7]
• 1994 – Gliese 229B is the first Substellar Mass Object to be unquestionably identified.
• 1997 – The 1997 Asian financial crisis causes a crash in the Dow Jones Industrial Average.
• 1999 – Gunmen open fire in the Armenian Parliament, killing the Prime Minister and seven others.
• 2014 – Britain withdraws from Afghanistan at the end of Operation Herrick, after 12 years four months and seven days.
• 2017 – Catalonia declares independence from Spain.
• 2018 – A gunman opens fire on a Pittsburgh synagogue killing eleven and injuring six, including four police officers.
• 2018 – Leicester City F.C. owner Vichai Srivaddhanaprabha dies in a helicopter crash along with four others after a Premier League match against West Ham United at the King Power Stadium in Leicester, England.^[8]
• 2019 – Islamic State of Iraq and the Levant founder and leader Abu Bakr al-Baghdadi kills himself and three children by detonating a suicide vest during the U.S. military Barisha raid in northwestern Syria.^[9][10]

• 892 – Emperor Ai of Tang, Chinese emperor (d. 908)
• 921 – Chai Rong, Chinese emperor (d. 959)
• 1156 – Raymond VI, Count of Toulouse (d. 1222)
• 1335 – Taejo of Joseon (d. 1408)
• 1401 – Catherine of Valois (d. 1437)
• 1561 – Mary Sidney, English writer, patroness and translator (d. 1621)
• 1572 – Marie Elisabeth of France, French princess (d. 1578)

• 1615 – Christian I, Duke of Saxe-Merseburg, (d. 1691)
• 1661 – Fyodor Apraksin, Russian admiral (d. 1728)
• 1703 – Johann Gottlieb Graun, German violinist and composer (d. 1771)
• 1744 – Mary Moser, English painter and academic (d. 1819)
• 1760 – August Neidhardt von Gneisenau, Prussian field marshal (d. 1831)
• 1765 – Nancy Storace, English soprano (d. 1817)
• 1782 – Niccolò Paganini, Italian violinist and composer (d. 1840)
• 1806 – Juan Seguín, American colonel, judge, and politician, 101st Mayor of San Antonio (d. 1890)
• 1811 – Stevens T. Mason, American lawyer and politician, 1st Governor of Michigan (d. 1843)
• 1811 – Isaac Singer, American actor and businessman, founded the Singer Corporation (d. 1875)
• 1814 – Daniel H. Wells, American religious leader and politician, 3rd Mayor of Salt Lake City (d. 1891)
• 1838 – John Davis Long, American lawyer and politician, 34th United States Secretary of the Navy (d. 1915)
• 1842 – Giovanni Giolitti, Italian politician, 13th Prime Minister of Italy (d. 1928)
• 1844 – Klas Pontus Arnoldson, Swedish journalist and politician, Nobel Prize laureate (d. 1916)
• 1854 – William Alexander Smith, Scottish religious leader, founded the Boys' Brigade (d. 1914)
• 1858 – Elliott Lewis, Australian politician, 19th Premier of Tasmania (d. 1935)
• 1858 – Saitō Makoto, Japanese admiral and politician, 30th Prime Minister of Japan (d. 1936)
• 1858 – Theodore Roosevelt, American colonel and politician, 26th President of the United States, Nobel Prize laureate (d. 1919)
• 1865 – Charles Spencelayh, English painter and academic (d. 1958)
• 1868 – William Gillies, Australian politician, 21st Premier of Queensland (d. 1928)
• 1877 – Walt Kuhn, American painter and academic (d. 1949)
• 1877 – George Thompson, English cricketer and umpire (d. 1943)
• 1884 – Shirō Takasu, Japanese admiral (d. 1944)
• 1885 – Sigrid Hjertén, Swedish painter (d. 1948)
• 1890 – Toshinari Shōji, Japanese general (d. 1974)
• 1894 – Agda Helin, Swedish actress (d. 1984)
• 1894 – Oliver Leese, English-Welsh general (d. 1978)
• 1894 – Fritz Sauckel, German sailor and politician (d. 1946)
• 1894 – Ye Shengtao, Chinese writer, educator, and politician (d. 1988)^[11]

• 1904 – Riho Lahi, Estonian journalist and author (d. 1995)
• 1906 – Peter Blume, Belarusian-American painter and sculptor (d. 1992)
• 1906 – Earle Cabell, American banker and politician, Mayor of Dallas (d. 1975)
• 1906 – Kazuo Ohno, Japanese dancer and educator (d. 2010)
• 1908 – Lee Krasner, American painter (d. 1984)^[12]
• 1910 – Jack Carson, Canadian-American actor and singer (d. 1963)
• 1910 – Margaret Hutchinson Rousseau, American chemical engineer (d. 2000)
• 1911 – Leif Erickson, American actor (d. 1986)^[12]
• 1913 – Joe Medicine Crow, American anthropologist, historian, and author (d. 2016)
• 1913 – Luigi Piotti, Italian race car driver (d. 1971)
• 1914 – Ahmet Kireççi, Turkish wrestler (d. 1979)
• 1914 – Dylan Thomas, Welsh poet and playwright (d. 1953)^[12]
• 1915 – Harry Saltzman, Canadian-French production manager and producer (d. 1994)
• 1917 – Augustine Harris, English bishop (d. 2007)
• 1917 – Oliver Tambo, South African lawyer and politician (d. 1993)
• 1918 – Mihkel Mathiesen, Estonian engineer and politician (d. 2003)
• 1918 – Teresa Wright, American actress and singer (d. 2005)
• 1920 – Nanette Fabray, American actress, singer, and dancer (d. 2018)^[12]
• 1920 – K. R. Narayanan, Indian lawyer and politician, 10th President of India (d. 2005)
• 1921 – Warren Allen Smith, American journalist, author, and activist (d. 2017)
• 1922 – Poul Bundgaard, Danish actor and singer (d. 1998)
• 1922 – Ruby Dee, American actress and poet (d. 2014)
• 1922 – Michel Galabru, French actor and playwright (d. 2016)
• 1922 – Ralph Kiner, American baseball player and sportscaster (d. 2014)^[12]
• 1923 – Roy Lichtenstein, American painter and sculptor (d. 1997)^[12]
• 1923 – Ned Wertimer, American actor (d. 2013)
• 1924 – Bonnie Lou, American singer-songwriter (d. 2015)
• 1925 – Warren Christopher, American soldier, lawyer, and politician, 63rd United States Secretary of State (d. 2011)
• 1925 – Jane Connell, American actress and singer (d. 2013)
• 1925 – Paul Fox, English broadcaster (d. 2024)
• 1925 – Monica Sims, English radio host and producer (d. 2018)
• 1926 – Boris Chetkov, Russian painter (d. 2010)
• 1926 – Henri Fertet, French Resistance fighter (d. 1943)^[13]
• 1926 – H. R. Haldeman, American businessman and diplomat, 4th White House Chief of Staff (d. 1993)
• 1926 – Takumi Shibano, Japanese author and translator (d. 2010)
• 1927 – Dominick Argento, American composer and educator (d. 2019)
• 1928 – Gilles Vigneault, Canadian singer-songwriter and poet
• 1929 – Myra Carter, American actress (d. 2016)
• 1929 – Bill George, American football player (d. 1982)
• 1929 – Maurice Robert Johnston, English general and politician, Lord Lieutenant of Wiltshire
• 1930 – Leo Baxendale, English cartoonist (d. 2017)
• 1930 – Barry Supple, English historian and academic
• 1931 – Nawal El Saadawi, Egyptian physician, psychiatrist, and author (d. 2021)
• 1931 – Anatoliy Zayaev, Ukrainian footballer and manager (d. 2012)
• 1932 – Jean-Pierre Cassel, French actor (d. 2007)
• 1932 – Harry Gregg, Northern Irish footballer and manager (d. 2020)
• 1932 – Dolores Moore, American baseball player (d. 2000)
• 1932 – Sylvia Plath, American poet, novelist, and short story writer (d. 1963)^[14]
• 1933 – Floyd Cramer, American singer and pianist (d. 1997)
• 1933 – Ryō Hanmura, Japanese author (d. 2002)
• 1934 – Giorgos Konstantinou, Greek actor, director, and screenwriter
• 1935 – Maurício de Sousa, Brazilian journalist and cartoonist
• 1935 – Charlie Tagawa, Japanese-American banjo player and educator (d. 2017)
• 1936 – Neil Sheehan, American journalist and author^[15] (d. 2021)
• 1937 – Alma Powell, American audiologist (d. 2024)^[16][17]
• 1938 – Lara Parker, American actress and author (d. 2023)
• 1939 – John Cleese, English actor, comedian, screenwriter and producer^[18]
• 1939 – Suzy Covey, American scholar and academic (d. 2007)
• 1939 – Dallas Frazier, American country music singer-songwriter (d. 2022)
• 1940 – John Gotti, American mob boss (d. 2002)
• 1940 – Maxine Hong Kingston, American author and academic
• 1941 – Dave Costa, American football player (d. 2013)
• 1941 – Warren Ryan, Australian rugby league player, coach, and sportscaster
• 1941 – Dick Trickle, American race car driver (d. 2013)
• 1942 – Lee Greenwood, American singer-songwriter^[19]
• 1942 – Janusz Korwin-Mikke, Polish journalist and politician
• 1943 – Carmen Argenziano, American actor and producer (d. 2019)
• 1943 – Jerry Rook, American basketball player and coach (d. 2019)
• 1944 – J. A. Jance, American author and poet
• 1945 – Arild Andersen, Norwegian bassist and composer
• 1945 – Luiz Inácio Lula da Silva, Brazilian union leader and politician, 35 and 39th President of Brazil^[12]
• 1945 – Carrie Snodgress, American actress (d. 2004)
• 1946 – Peter Martins, Danish dancer and choreographer
• 1946 – Steven R. Nagel, American colonel, engineer, and astronaut (d. 2014)
• 1946 – Ivan Reitman, Slovak-Canadian actor, director, and producer (d. 2022)^[12]
• 1947 – Terry A. Anderson, American journalist (d. 2024)^[20]
• 1948 – Kevin Borich, New Zealand-Australian guitarist and songwriter^[21]
• 1949 – Garry Tallent, American bass player and record producer^[19]
• 1950 – Michael Driscoll, English economist and academic
• 1950 – Fran Lebowitz, American author^[19]
• 1950 – Július Šupler, Slovak ice hockey player and coach
• 1950 – A. N. Wilson, English journalist, historian, and author
• 1951 – K. K. Downing, English guitarist and songwriter^[19]
• 1951 – Carlos Frenk, Mexican-English physicist, cosmologist, and academic
• 1951 – Nancy Jacobs, American politician
• 1951 – Jayne Kennedy, American model, actress, and sportscaster^[19]
• 1952 – Roberto Benigni, Italian actor, director, and screenwriter^[19]
• 1952 – Francis Fukuyama, American political scientist, economist, and author
• 1952 – Atsuyoshi Furuta, Japanese footballer
• 1952 – Topi Sorsakoski, Finnish singer-songwriter (d. 2011)
• 1953 – Peter Firth, English actor^[19]
• 1953 – Robert Picardo, American actor, director, and screenwriter^[19]
• 1954 – Jan Duursema, American illustrator
• 1954 – Mike Kelley, American artist and musician (d. 2012)
• 1954 – Chris Tavaré, English cricketer and biologist
• 1955 – Debra Bowen, American lawyer and politician, 31st Secretary of State of California
• 1956 – Patty Sheehan, American golfer
• 1956 – Babis Tsertos, Greek singer-songwriter and bouzouki player
• 1957 – Glenn Hoddle, English footballer and manager
• 1957 – Peter Marc Jacobson, American actor, director, and producer
• 1958 – Gordon Cowans, English footballer
• 1958 – David Hazeltine, American pianist and composer
• 1958 – Simon Le Bon, English singer-songwriter^[19]
• 1958 – Jonathan Shapiro, South African political cartoonist who uses the pseudonym Zapiro
• 1958 – Felix Wurman, American cellist and composer (d. 2009)
• 1958 – Donnell Thompson, American football player (d. 2024)^[22]
• 1959 – Rick Carlisle, American basketball player and coach
• 1960 – Tom Nieto, American baseball player, coach, and manager
• 1963 – David Hall, Australian horse trainer
• 1963 – Marla Maples, American model and actress^[12]
• 1963 – Tom McKean, Scottish runner
• 1964 – Mary T. Meagher, American swimmer
• 1964 – Mark Taylor, Australian cricketer and sportscaster
• 1964 – Ian Wells, English footballer (d. 2013)
• 1965 – Mohan Kapoor, Indian television and film actor
• 1966 – Steve Almond, American author and educator
• 1966 – Kit Malthouse, English accountant and politician
• 1966 – Hege Nerland, Norwegian lawyer and politician (d. 2007)
• 1966 – Masanobu Takashima, Japanese actor
• 1967 – Simone Moro, Italian mountaineer and pilot
• 1967 – Dejan Raičković, Montenegrin footballer and manager
• 1967 – Scott Weiland, American singer-songwriter (d. 2015)^[12]
• 1968 – Alain Auderset, Swiss author and illustrator
• 1968 – Dileep, Indian actor and producer
• 1968 – Vinny Samways, English footballer and manager
• 1969 – Marek Napiórkowski, Polish jazz guitarist and composer
• 1969 – Michael Tarnat, German footballer
• 1970 – Karl Backman, Swedish guitarist and songwriter
• 1970 – Felix Bwalya, Zambian boxer (d. 1997)
• 1970 – Adrian Erlandsson, Swedish drummer
• 1970 – Jonathan Stroud, English author
• 1970 – Ruslana Taran, Ukrainian sailor
• 1971 – Stefano Guidoni, Italian footballer
• 1971 – Jorge Soto, Peruvian footballer
• 1971 – Theodoros Zagorakis, Greek footballer and politician
• 1972 – Lee Clark, English footballer and manager
• 1972 – Elissa, Lebanese singer
• 1972 – Evan Coyne Maloney, American director, producer, and screenwriter
• 1972 – Maria Mutola, Mozambican runner and coach
• 1972 – Brad Radke, American baseball player
• 1973 – Jason Johnson, American baseball player
• 1973 – Semmy Schilt, Dutch kick-boxer and mixed martial artist
• 1975 – Predrag Drobnjak, Montenegrin basketball player^[23]
• 1975 – Nicola Mazzucato, Italian rugby player and coach
• 1975 – Aron Ralston, American mountaineer and engineer
• 1976 – Bobby Fish, American professional wrestler
• 1976 – Maneet Chauhan, Indian-American chef and author
• 1976 – Wilson Júnior, Brazilian footballer
• 1977 – Jiří Jarošík, Czech footballer
• 1977 – Sheeri Rappaport, American actress^[19]
• 1977 – Kumar Sangakkara, Sri Lankan cricketer
• 1978 – Sergei Samsonov, Russian ice hockey player and scout
• 1978 – Vanessa-Mae, Singaporean-English violinist and skier
• 1979 – Hiroyuki Yamamoto, Japanese footballer
• 1980 – Sayuri Osuga, Japanese speed skater and cyclist
• 1980 – Tanel Padar, Estonian singer-songwriter and guitarist
• 1980 – Henriett Seth F., Hungarian autistic savant artist and author^[24]
• 1981 – Salem Al Fakir, Swedish singer and keyboard player
• 1981 – Sririta Jensen, Thai actress and model
• 1981 – Volkan Demirel, Turkish footballer
• 1981 – Kristi Richards, Canadian skier
• 1982 – Patrick Fugit, American actor and producer
• 1982 – Takashi Tsukamoto, Japanese actor and singer
• 1983 – Brent Clevlen, American baseball player
• 1983 – Martín Prado, Venezuelan baseball player
• 1984 – Yi Jianlian, Chinese basketball player
• 1984 – Kostas Kapetanos, Greek footballer
• 1984 – Kelly Osbourne, English television personality^[19]
• 1984 – Brady Quinn, American football player
• 1984 – Emilie Ullerup, Danish-Canadian actress
• 1985 – Sirli Hanni, Estonian biathlete
• 1985 – Sandra Volk, Slovenian tennis player
• 1985 – Alex Soros, American investor and philanthropist^[25]
• 1986 – Chris Butler, American ice hockey player^[26]
• 1986 – Anna Cruz, Spanish basketball player^[27]
• 1986 – Christine Evangelista, American actress^[19]
• 1986 – Crystal Langhorne, American basketball player^[28]
• 1986 – Jon Niese, American baseball player
• 1986 – Matty Pattison, South African-English footballer
• 1986 – David Warner, Australian cricketer
• 1986 – Lou Williams, American basketball player^[29]
• 1987 – Thelma Aoyama, Japanese singer
• 1987 – Björn Barrefors, Swedish decathlete and heptathlete
• 1987 – Andrew Bynum, American basketball player
• 1987 – Guillaume Franke, French-German rugby player
• 1988 – Brady Ellison, American archer
• 1988 – Viktor Genev, Bulgarian footballer
• 1988 – Illimar Pärn, Estonian ski jumper
• 1988 – Evan Turner, American basketball player
• 1989 – Mark Barron, American football player
• 1990 – Alex Bentley, American-Belarusian basketball player^[30]
• 1990 – Dimitrios Gkourtsas, Greek footballer
• 1990 – Oktovianus Maniani, Indonesian footballer
• 1991 – Shohei Takahashi, Japanese footballer
• 1992 – Stephan El Shaarawy, Italian footballer
• 1992 – Emily Hagins, American director, producer, and screenwriter
• 1992 – Brandon Saad, American ice hockey player
• 1992 – Daniel Sams, Australian cricketer^[31]
• 1993 – Troy Gentile, American actor^[19]
• 1993 – Kiefer Ravena, Filipino basketball player
• 1994 – Rasmus Ristolainen, Finnish ice hockey player^[32]
• 1995 – Leon Draisaitl, German ice hockey player^[33]
• 1996 – Rasmus Andersson, Swedish ice hockey player^[34]
• 1996 – Kim Woo-seok, South Korean singer and actor^[35]
• 1997 – Lonzo Ball, American basketball player
• 1997 – James TW, English singer-songwriter^[36]
• 1999 – Haruka Kudo, Japanese singer and actress

• 939 – Æthelstan, English king^[37]
• 1052 – Qirwash ibn al-Muqallad, Uqaylid emir^[38]
• 1269 – Ulrich III, Duke of Carinthia (b. c.1220)
• 1272 – Hugh IV, Duke of Burgundy (b. 1213)
• 1277 – Walter de Merton, Lord Chancellor of England
• 1303 – Beatrice of Castile, wife of King Afonso III of Portugal
• 1312 – John II, Duke of Brabant (b. 1275)
• 1326 – Hugh le Despenser, 1st Earl of Winchester (b. 1262)
• 1327 – Elizabeth de Burgh, queen of Robert the Bruce^[39]
• 1329 – Mahaut, Countess of Artois (b. 1268)
• 1331 – Abulfeda, Arab historian and geographer (b. 1273)
• 1430 – Vytautas, Lithuanian ruler (b. 1350)
• 1439 – Albert II of Germany (b. 1397)
• 1441 – Margery Jourdemayne, executed for treasonable witchcraft
• 1449 – Ulugh Beg, Persian astronomer, mathematician and sultan (b. 1394)
• 1485 – Rodolphus Agricola, Dutch philosopher, poet and educator (b. 1443)
• 1505 – Ivan III of Russia (b. 1440)
• 1513 – George Manners, 11th Baron de Ros, English nobleman
• 1553 – Michael Servetus, Spanish physician and theologian (b. 1511)
• 1561 – Lope de Aguirre, Spanish explorer (b. 1510)
• 1573 – Laurentius Petri, Swedish archbishop (b. 1499)

• 1605 – Akbar, Mughal emperor (b. 1542)
• 1613 – Gabriel Báthory, Prince of Transylvania (b. 1589)
• 1617 – Ralph Winwood, English lawyer and politician, English Secretary of State (b. 1563)
• 1666 – Robert Hubert, French watchmaker (b. 1640)
• 1670 – Vavasor Powell, Welsh minister (b. 1617)
• 1674 – Hallgrímur Pétursson, Icelandic minister and poet (b. 1614)
• 1675 – Gilles de Roberval, French mathematician and academic (b. 1602)
• 1789 – John Cook, American farmer and politician, 6th Governor of Delaware (b. 1730)
• 1812 – Isaac Brock, British army officer and administrator, Lieutenant Governor of Upper Canada (b. 1769)
• 1816 – Santō Kyōden, Japanese poet and painter (b. 1761)
• 1880 – Thrasyvoulos Zaimis, Greek soldier and politician, 48th Prime Minister of Greece (b. 1822)

• 1917 – Arthur Rhys-Davids, English lieutenant and pilot (b. 1897)
• 1926 – Warren Wood, American golfer and soldier (b. 1887)
• 1927 – Squizzy Taylor, Australian gangster (b. 1888)
• 1929 – Théodore Tuffier, French surgeon (b. 1857)
• 1930 – Ellen Hayes, American mathematician and astronomer (b. 1851)
• 1935 – Ernest Eldridge, English race car driver (b. 1897)
• 1942 – Helmuth Hübener, German activist (b. 1925)
• 1944 – Judith Auer, German World War II resistance fighter (b. 1905)^[40]
• 1947 – William Fay, Irish actor and producer, co-founded the Abbey Theatre (b. 1872)
• 1949 – Marcel Cerdan, Algerian-French boxer (b. 1916)
• 1953 – Thomas Wass, English cricketer (b. 1873)
• 1957 – James McGirr, Australian politician, 28th Premier of New South Wales (b. 1890)
• 1962 – Rudolf Anderson, American soldier and pilot (b. 1927)
• 1962 – Enrico Mattei, Italian businessman and politician (b. 1906)
• 1968 – Lise Meitner, Austrian-English physicist and academic (b. 1878)^[41]
• 1974 – C. P. Ramanujam, Indian mathematician and academic (b. 1938)
• 1975 – Rex Stout, American detective novelist (b. 1886)
• 1977 – James M. Cain, American journalist and author (b. 1892)
• 1980 – Judy LaMarsh, Canadian soldier, lawyer, and politician, 42nd Secretary of State for Canada (b. 1924)
• 1980 – John Hasbrouck Van Vleck, American physicist and mathematician, Nobel Prize laureate (b. 1899)
• 1982 – Miguel Ydígoras Fuentes, President of Guatemala (1958–1963) (b. 1895)
• 1988 – Charles Hawtrey, English actor, singer, and pianist (b. 1914)
• 1990 – Xavier Cugat, Spanish-American violinist, bandleader, and actor (b. 1900)
• 1990 – Jacques Demy, French actor, singer, director, and screenwriter (b. 1931)
• 1990 – Elliott Roosevelt, American general and author (b. 1910)
• 1990 – Ugo Tognazzi, Italian actor, director, and screenwriter (b. 1922)
• 1991 – George Barker, English author and poet (b. 1913)
• 1992 – David Bohm, American-English physicist and philosopher (b. 1917)
• 1992 – Allen R. Schindler, Jr. American sailor (b. 1969)
• 1996 – Arthur Tremblay, Canadian lawyer and politician (b. 1917)
• 1997 – Mahala Andrews, British vertebrae palaeontologist (b. 1939)^[42]
• 1999 – Robert Mills, American physicist and academic (b. 1927)
• 1999 – Charlotte Perriand, French architect and designer (b. 1903)
• 2000 – Walter Berry, Austrian lyric bass-baritone (b. 1929)
• 2001 – Pradeep Kumar, Indian actor, director, and producer (b. 1925)
• 2002 – Tom Dowd, American record producer and engineer (b. 1925)
• 2002 – Valve Pormeister, Estonian architect (b. 1922)
• 2003 – Rod Roddy, American game show announcer (b. 1937)
• 2003 – Stephanie Tyrell, American songwriter and producer (b. 1949)
• 2004 – Lester Lanin, American bandleader (b. 1907)
• 2004 – Paulo Sérgio Oliveira da Silva, Brazilian footballer (b. 1974)
• 2004 – Zdenko Runjić, Croatian songwriter and producer (b. 1942)
• 2005 – Jerry Cooke, Ukrainian-American photographer and journalist (b. 1921)
• 2006 – Jozsef Gregor, Hungarian opera singer (b. 1940)
• 2006 – Reko Lundán, Finnish journalist and author (b. 1969)
• 2006 – Marlin McKeever, American football player (b. 1940)
• 2006 – Joe Niekro, American baseball player (b. 1944)
• 2006 – Brad Will, American journalist and activist (b. 1970)
• 2007 – Moira Lister, South African actress (b. 1923)
• 2008 – Chris Bryant, English actor and screenwriter (b. 1936)
• 2008 – Ray Ellis, American conductor and producer (b. 1923)
• 2008 – Frank Nagai, Japanese singer (b. 1932)
• 2008 – Roy Stewart, Jamaican-English actor and stuntman (b. 1925)
• 2009 – John David Carson, American actor (b. 1952)
• 2009 – August Coppola, American author and academic (b. 1934)
• 2009 – David Shepherd, English cricketer and umpire (b. 1940)
• 2009 – Taylor Mitchell, Canadian singer and songwriter (b. 1990)^[43]
• 2010 – Néstor Kirchner, Argentinian lawyer and politician, 51st President of Argentina (b. 1950)
• 2011 – James Hillman, American psychologist and author (b. 1926)
• 2011 – Robert Pritzker, American businessman, co-founded Marmon Group (b. 1926)
• 2012 – Terry Callier, American singer-songwriter and guitarist (b. 1945)
• 2012 – Angelo Maria Cicolani, Italian engineer and politician (b. 1952)
• 2012 – Regina Dourado, Brazilian actress (b. 1952)
• 2012 – Hans Werner Henze, German composer and educator (b. 1926)
• 2012 – Rodney S. Quinn, American colonel, pilot, and politician, 44th Secretary of State of Maine (b. 1923)
• 2012 – Göran Stangertz, Swedish actor and director (b. 1944)
• 2013 – Noel Davern, Irish lawyer and politician, Minister for Education and Skills (b. 1945)
• 2013 – Leonard Herzenberg, American immunologist, geneticist, and academic (b. 1931)
• 2013 – Luigi Magni, Italian director and screenwriter (b. 1928)
• 2013 – Lou Reed, American singer-songwriter, guitarist, producer, and actor (b. 1942)
• 2013 – Michael Wilkes, English general and politician, Lieutenant Governor of Jersey (b. 1940)
• 2013 – Vinko Coce, Croatian opera and pop singer (b. 1954)
• 2014 – Daniel Boulanger, French actor and screenwriter (b. 1922)
• 2014 – Shin Hae-chul, South Korean singer-songwriter and producer (b. 1968)
• 2014 – Starke Taylor, American soldier and politician, mayor of Dallas (b. 1922)
• 2015 – Ayerdhal, French author (b. 1959)
• 2015 – Ranjit Roy Chaudhury, Indian pharmacologist and academic (b. 1930)
• 2015 – Betsy Drake, French-American actress and singer (b. 1923)
• 2015 – Philip French, English journalist, critic, and producer (b. 1933)^[44]
• 2016 – Takahito, Prince Mikasa, member of the Imperial Family of Japan (b. 1915)
• 2018 – Vichai Srivaddhanaprabha, chairman of Leicester City F.C^[45][46] (b. 1958)
• 2019 – Abu Bakr al-Baghdadi, leader of the Islamic State of Iraq and the Levant (ISIL); suicide (b. 1971)^[9][10]
• 2023 – Li Keqiang, premier of China (b. 1955)^[47]

• Christian feast day:
  • Abbán
  • Abraham the Poor
  • Frumentius (Roman Catholic Church)
  • Gaudiosus of Naples
  • Kaleb of Axum
  • Namatius (Namace)
  • Oran of Iona
  • October 27 (Eastern Orthodox liturgics)
• Černová Tragedy Day (Slovakia)
• Flag Day (Greece)
• Independence Day (Saint Vincent and the Grenadines), celebrates the independence of Saint Vincent and the Grenadines from United Kingdom in 1979.
• International Religious Freedom Day (United States)^[48]
• National Black Cat Day (United Kingdom)^[49]
• Navy Day (United States) (unofficial, official date is October 13)
• World Day for Audiovisual Heritage^[50]

Wikimedia Commons has media related to October 27.

• "On This Day". BBC.
• The New York Times: On This Day
• "Historical Events on October 27". OnThisDay.com.