Events by name

18,274 events with something written about them, in alphabetical order. Page 68 of 92. Or browse by year.

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• 1975 CEOPEC siegeOn 21 December 1975, six militants attacked the semi-annual meeting of OPEC leaders in Vienna, Austria; they…
• 2001 CEOSDEM 2001Free and Open source Software Developers' European Meeting (FOSDEM) is an annual software engineering…
• 1827 CEOakville foundedOakville is a town and the seat of Halton Region in Ontario, Canada. It borders Burlington to the southwest…
• 2003 CEOakwood mutinyOn July 27, 2003, the Oakwood mutiny was led by a group of about 300 armed defectors from the Armed Forces of…
• 1999 CEObafemi Awolowo University massacreThe Obafemi Awolowo University massacre was the mass murder of students of Obafemi Awolowo University in…
• 300 CEObelisk of Axum (monument) builtThe Obelisk of Axum (Tigrinya: ሓወልቲ ኣኽሱም, romanized: ḥawelti Akhsum; Amharic: የአክሱም ሐውልት, romanized: Ye’Åksum…
• 600 BCEObelisk of Montecitorio (monument) builtThe Obelisk of Montecitorio (Italian: Obelisco di Montecitorio), also known as Solare, is an ancient…
• 1955 CEObelisk of São Paulo (mausoleum) builtObelisk of São Paulo (in Portuguese: Obelisco de São Paulo) or Obelisk of Ibirapuera (in Portuguese: Obelisco…
• 1500 BCEObelisk of Theodosius (monument) builtThe Obelisk of Theodosius (Greek: Οβελίσκος του Θεοδόσιου Α΄, Turkish: Dikilitaş) is the Ancient Egyptian…
• 1979 CEObject "Klivazh"Klivazh is the site of an underground peaceful nuclear explosion in the Soviet program of Nuclear Explosions…
• 1995 CEOborci massacreThe Oborci massacre occurred on September 13, 1995, when soldiers from the 1st Krajina Corps of the Army of…
• 2008 CEOccupation of PotiThe Occupation of Poti was a series of Russian strikes against the Georgian port of Poti during the…
• 1984 CEOccupation of the Hainburger AuThe Occupation of the Hainburger Au wetlands in December 1984 marked a turning point for environmental…
• 2023 CEOccupy Julorbi HouseOccupy Julorbi House was a Ghanaian three-day protest which started off as an online protest on the social…
• 2011 CEOccupy Wall StreetOccupy Wall Street (O.W.S.) was a left-wing populist and progressive movement against economic inequality…
• 2014 CEOcean Researcher VRV Ocean Researcher V (traditional Chinese: 海研五號; simplified Chinese: 海研五号; pinyin: Hǎiyán Wǔ Hào) was a…
• 1823 CEOchomogo WarThe Ochomogo War was a civil war fought in Costa Rica, the first in its history, and was fought shortly after…
• 1944 CEOchota massacreThe Ochota massacre (in Polish: Rzeź Ochoty – "Ochota slaughter") was a wave of German-orchestrated mass…
• 1920 CEOcoee massacreThe Ocoee massacre was an act of mass racial violence in November 1920. During the massacre, a white mob…
• 1187 CEOctober 1187 papal electionThe October 1187 papal election (held October 21) was convoked after the death of Pope Urban III. He and the…
• 1503 CEOctober 1503 papal conclaveThe October 1503 conclave elected Cardinal Giuliano della Rovere as Pope Julius II to succeed Pope Pius III.…
• 1900 CEOctober 1900 Carlist uprisingThe Carlist uprising of October 1900 was an attempted armed insurrection that originated in Badalona, a city…
• 1978 CEOctober 1978 conclaveA conclave was held from 14 to 16 October 1978 to elect a new pope to succeed John Paul I, who had died on 28…
• 2009 CEOctober 2009 Afghanistan earthquakeA 6.2 magnitude earthquake occurred in Afghanistan on October 22, 2009, at 19:51:27 UTC. The maximum Mercalli…
• 2010 CEOctober 2010 Sumatra earthquake and tsunamiThe 2010 Mentawai earthquake occurred with a moment magnitude of 7.8 on 25 October off the western coast of…
• 2013 CEOctober 2013 Volgograd bus bombingThe October 2013 Volgograd bus bombing was a suicide bombing which occurred on 21 October 2013 in the city of…
• 2016 CEOctober 2016 Central Italy earthquakesA series of major earthquakes struck Central Italy between the Marche and Umbria regions in October 2016. The…
• 2017 CEOctober 2017 Mogadishu bombingsOn 14 October 2017, two truck bombings took place in Mogadishu, the capital of Somalia, killing at least 587…
• 2022 CEOctober 2022 Mogadishu bombingsOn 29 October 2022, 121 people were killed and over 300 were injured by a double car bombing in Somalia's…
• 2024 CEOctober 2024 Abu Hussein school attackOn 17 October 2024, the Israel Defense Forces (IDF) bombed the UNRWA-run Abu Hussein primary school, which…
• 2024 CEOctober 2024 Rufaida school attackOn 10 October 2024, the Israel Defense Forces (IDF) bombed Rufaida school-turned-shelter in Deir al-Balah in…
• 2023 CEOctober 7 attacksOn October 7, 2023, a series of coordinated armed incursions from the blockaded Gaza Strip into the Gaza…
• 1590 CEOctober–December 1590 papal conclaveA conclave held from 8 October to 5 December 1590 ended with the election of Gregory XIV was elected as the…
• 1987 CEOdaeyang mass suicideThe Evangelical Baptist Church (EBC) of Korea (Korean: 기독교복음침례회; officially Korean Evangelical Baptist Church…
• 1418 CEOdawara Castle builtOdawara Castle (小田原城, Odawara-jō) is a reconstructed Japanese castle in the city of Odawara in Kanagawa…
• 1355 CEOdense foundedOdense ( OH-dən-sə, US also OH-thən-sə; Danish: [ˈoðˀn̩sə] ) is the third largest city in Denmark (after…
• 161 CEOdeon of Herodes Atticus settledThe Odeon of Herodes Atticus (Greek: Ωδείο Ηρώδου του Αττικού; also called Herodeion or Herodion; Greek…
• 2014 CEOdesa Trade Unions building fireIn early 2014, there were clashes between rival groups of protesters in the Ukrainian city of Odesa, during…
• 1500 CEOdesa foundedOdesa, also spelled Odessa, is the third-most populous city and municipality in Ukraine and a major seaport…
• 1919 CEOdessa OperationThe Odessa operation (1919) or the Odessa landing was a successful amphibious military operation by the White…
• 1400 CEOdina Mosque builtOdina Mosque (also known as Nasaf Katta Jome Mosque) is the oldest preserved architectural monument located…
• 1972 CEOestrich-Winkel foundedOestrich-Winkel (German pronunciation: [ˈøːstʁɪç ˈvɪŋkl̩]) is a town with roughly 12,000 inhabitants in the…
• 1148 CEOffenburg foundedOffenburg (German pronunciation: [ˈɔfn̩bʊʁk]; "open borough" - coat of arms showing open gates; Low…
• 1973 CEOfira Air BattleThe Ofira Air Battle was one of the first air battles of the Yom Kippur War. On 6 October 1973, Egypt…
• 1400 CEOgrodzieniec Castle builtOgrodzieniec Castle is a ruined medieval castle in Podzamcze, near Ogrodzieniec, the south-central region of…
• 2001 CEOhayoconOhayocon is a three-day anime convention typically held during January/February in Dayton, Ohio at the Dayton…
• 1870 CEOhio State University foundedThe Ohio State University (Ohio State, tOSU, or OSU) is a public research university in Columbus, Ohio…
• 2012 CEOikos University shootingOn April 2, 2012, 43-year-old One L. Goh killed seven people and injured three others at Oikos University, a…
• 1346 CEOkayama Castle builtOkayama Castle (岡山城, Okayama-jō) is a Japanese castle in the city of Okayama in Okayama Prefecture in Japan.…
• 1455 CEOkazaki Castle builtOkazaki Castle (岡崎城, Okazaki-jō) is a Japanese castle located in Okazaki, Aichi Prefecture, Japan. At the end…
• 1916 CEOkazaki foundedOkazaki (岡崎市, Okazaki-shi; Japanese pronunciation: [o.kaꜜ.(d)za.kʲi, -ka.(d)za.kʲi̥ꜜ.ɕi, -(d)zaꜜ.kʲi̥.ɕi]…
• 2013 CEOkhotsk Sea earthquakeThe 2013 Okhotsk Sea earthquake occurred with a moment magnitude of 8.3 at 15:44:49 local time (05:44:49 UTC)…
• 1995 CEOklahoma City bombingOn April 19, 1995, American anti-government extremist Timothy McVeigh, assisted by Terry Nichols, detonated a…
• 1889 CEOklahoma City foundedOklahoma City ( OH-klə-HOH-mə -⁠), often shortened to OKC, is the capital and most populous city in the U.S.…
• 1977 CEOklahoma Girl Scout murdersThe Oklahoma Girl Scout murders took place on the morning of June 13, 1977, at Camp Scott in Mayes County…
• 1810 CEOktoberfestOktoberfest (German pronunciation: [ɔkˈtoːbɐˌfɛst]; Bavarian: Oktobafest/d'Wiesn) is the world's largest…
• 1980 CEOktoberfest terror attackThe Oktoberfest bombing (German: Oktoberfest-Attentat) was a far-right terrorist attack. On 26 September…
• 1475 CEOlavinlinna Castle builtOlavinlinna (Finnish: [ˈolɑʋinˌlinːɑ]; Swedish: Olofsborg), also known as St. Olaf's Castle, is a…
• 700 BCEOlbia foundedPontic Olbia (Ancient Greek: Ὀλβία Ποντική; Ukrainian: Ольвія, romanized: Olviia) or simply Olbia is an…
• 950 CEOld Castle builtThe Old Palace (German: Altes Schloss) is a former castle located on the Schillerplatz in Stuttgart, Germany.…
• 1545 CEOld Fortress of Corfu builtThe Old Fortress of Corfu (Greek: Παλαιό Φρούριο, Venetian: Fortezza Vecchia) is a Venetian fortress in the…
• 1402 CEOld Mosque (Edirne) builtThe Old Mosque (Turkish: Eski Camii), also known as Grand Mosque (Turkish: Ulucami), is an early 15th-century…
• 1836 CEOld Royal Palace builtThe Old Royal Palace (Greek: Παλαιά Ανάκτορα, romanized: Palaiá Anáktora) is the first royal palace of modern…
• 320 CEOld St. Peter's Basilica builtOld St. Peter's Basilica consisted of the church buildings that stood, from the 4th to 16th centuries, where…
• 499 BCEOld Temple of Athena builtThe Old Temple of Athena or the Archaios Neos (Greek: Ἀρχαῖος Νεώς) was an archaic Greek limestone Doric…
• 1425 CEOld University of Leuven foundedThe Old University of Leuven is the name historians give to the university, or studium generale, founded in…
• 1962 CEOle Miss riot of 1962The Ole Miss riot of 1962 (September 30 – October 1, 1962), also known as the Battle of Oxford, was a race…
• 1974 CEOlean High School shootingThe Olean High School shooting was a school shooting that occurred on December 30, 1974, at Olean High School…
• 2022 CEOlenivka prison explosionOn 29 July 2022, Russian Armed Forces shelled a building housing Ukrainian prisoners of war in a…
• 1017 CEOlomouc foundedOlomouc (Czech pronunciation: [ˈolomouts]; German: Olmütz) is a city in the Czech Republic. It has about…
• 1998 CEOmagh bombingA car bombing took place in the town of Omagh in County Tyrone, Northern Ireland on 15 August 1998. It was…
• 1954 CEOmar Ali Saifuddien Mosque builtThe Omar Ali Saifuddien Mosque (Malay: Masjid Omar Ali Saifuddien). or unofficially Sultan Omar Ali Saifuddin…
• 1716 CEOmsk foundedOmsk is the administrative center and largest city of Omsk Oblast, Russia. It is situated in southwestern…
• 1352 CEOnze-Lieve-Vrouwekathedraal (church building) builtThe Cathedral of Our Lady (Dutch: Onze-Lieve-Vrouwekathedraal) is a Roman Catholic cathedral in Antwerp…
• 1868 CEOpelousas MassacreThe Opelousas massacre, or St. Landry Massacre, which began on September 28, 1868, was one of the bloodiest…
• 1965 CEOperación 90Operación 90 (Operation Ninety) was the first Argentine ground expedition to the South Pole, carried out in…
• 2007 CEOperation AchillesOperation Achilles was a NATO operation, part of the War in Afghanistan. Its objective was to clear Helmand…
• 1917 CEOperation AlbionOperation Albion was a German air, land and naval operation in the First World War, against Russian forces in…
• 2002 CEOperation AnacondaOperation Anaconda or the Battle of Shah-i-Kot was a military operation that took place in early March 2002…
• 2014 CEOperation AshuraLiberation of Jurf Al Sakhar, codenamed Operation Ashura (Arabic: عملية عاشوراء), was a two-day military…
• 1975 CEOperation BabyliftOperation Babylift was a mass evacuation of children from South Vietnam to the United States and other…
• 1967 CEOperation BribieOperation Bribie (17–18 February 1967), also known as the Battle of Ap My An, was fought during the Vietnam…
• 1951 CEOperation Buster-JangleOperation Buster–Jangle was a series of seven (six atmospheric, one cratering) nuclear weapons tests…
• 1994 CEOperation BøllebankThe Operation Bøllebank (English: Operation Bully Bashing) is the name given to the military confrontation…
• 1943 CEOperation CartwheelOperation Cartwheel (1943–1944) was a major military operation undertaken by the Allies in the Pacific…
• 1945 CEOperation CowboyOperation Cowboy was fought in the town of Hostau, Sudetenland (now Hostouň in the Czech Republic), on 28…
• 1966 CEOperation CrimpOperation Crimp (8–14 January 1966), also known as the Battle of the Ho Bo Woods, was a joint US-Australian…
• 1946 CEOperation CrossroadsOperation Crossroads was a pair of nuclear weapon tests conducted by the United States at Bikini Atoll in…
• 1940 CEOperation CycleOperation Cycle is the name of the evacuation of Allied troops from Le Havre, in the Pays de Caux of Upper…
• 1995 CEOperation FlashOperation Flash (Croatian: Операција Бљесак, romanized: Operacija Bljesak) was a brief Croatian Army (HV)…
• 1943 CEOperation FustianOperation Fustian was an airborne forces operation undertaken during the Allied invasion of Sicily in July…
• 1978 CEOperation GalaxiaOperation Galaxia (Spanish: Operación Galaxia) was the plan which preceded the 23-F attempted coup d'état in…
• 1943 CEOperation GarlicOperation Garlic was an operation to attack the Dortmund-Ems Canal by 617 Squadron carried out on 14-16…
• 2010 CEOperation HalmazagOperation Halmazag (Dari for "lightning") was an offensive operation by ISAF German-led troops in close…
• 1958 CEOperation Hardtack IIOperation Hardtack II was a series of 37 nuclear tests conducted by the United States in 1958 at the Nevada…
• 1942 CEOperation HarpoonOperation Harpoon (Battle of Pantelleria (Battaglia di Mezzo Giugno [Battle of mid-June]) was part of…
• 1943 CEOperation Harvest FestivalOperation Harvest Festival (German: Aktion Erntefest) was the murder of up to 43,000 Jews at the Majdanek…
• 1952 CEOperation HurricaneOperation Hurricane was the first test of a British atomic device. A plutonium implosion device was detonated…
• 1970 CEOperation Ivory CoastOperation Ivory Coast was a mission conducted by United States Special Operations Forces and other American…
• 1943 CEOperation JaywickOperation Jaywick was a special operation undertaken in the Second World War. In September 1943, 14 commandos…
• 1993 CEOperation MaslenicaOperation Maslenica was a Croatian Army offensive launched in January 1993 to retake territory in northern…
• 1993 CEOperation Medak PocketOperation Medak Pocket (Serbo-Croatian: Operacija Medački džep, Операција Медачки џеп), officially called by…
• 1918 CEOperation MichaelOperation Michael (German: Unternehmen Michael) was a major German military offensive during World War I that…
• 1995 CEOperation Mistral 2Operation Mistral 2, officially codenamed Operation Maestral 2, was a Croatian Army (HV) and Croatian Defence…
• 2010 CEOperation MoshtarakOperation Moshtarak (Dari for Together or Joint), also known as the Battle of Marjah, was an International…
• 1944 CEOperation Ostra BramaOperation Ostra Brama (Polish: Operacja „Ostra Brama”, lit. 'Operation Sharp Gate') was the Polish Home…
• 1942 CEOperation PedestalOperation Pedestal (Italian: Battaglia di Mezzo Agosto, Battle of mid-August), known in Malta as Il-Konvoj…
• 1957 CEOperation PlumbbobOperation Plumbbob was a series of nuclear tests that were conducted between May 28 and October 7, 1957, at…
• 1956 CEOperation RedwingOperation Redwing was a United States series of 17 nuclear test detonations from May to July 1956. They were…
• 1945 CEOperation SarajevoThe Sarajevo Operation was an operation by the Yugoslav Partisan Army which led to the liberation of Sarajevo…
• 1980 CEOperation Scorch SwordOperation Scorch Sword (Persian: عَمَلیاتِ شمشیرِ سوزان) was an Iranian airstrike on Iraq's Tuwaitha Nuclear…
• 1941 CEOperation SonnenblumeOperation Sonnenblume (Unternehmen Sonnenblume, "Operation Sunflower") was the name given to the dispatch of…
• 1943 CEOperation SparkOperation Iskra (Russian: операция Искра, lit. 'Operation Spark'), a Soviet military operation in January…
• 1965 CEOperation StarliteOperation Starlite (also known in Vietnam as Battle of Van Tuong) was the first major offensive action…
• 1995 CEOperation StormOperation Storm (Serbo-Croatian: Operacija Oluja / Операција Олуја) in August 1995 was the last major battle…
• 1991 CEOperation Swath-10Operation Swath-10 (Croatian: Operacija Otkos-10) was a military offensive undertaken by the Croatian Army…
• 1945 CEOperation Ten-GoOperation Kikusui I (菊水作戦, Kikusui Sakusen 1; Operation Chrysanthemum Water 1), best known as Operation…
• 1951 CEOperation ThunderboltOperation Thunderbolt, also known in China as the Defensive Battle of the Han River Southern Bank (Chinese…
• 1955 CEOperation WigwamOperation Wigwam involved a single test of the Mark 90 "Betty" nuclear bomb. It was conducted between…
• 1940 CEOperation WikingerOperation Viking (German: Unternehmen Wikinger) was a German naval sortie into the North Sea by six…
• 2015 CEOperation of Sidi AïchThe Sidi Aïch operation was an anti-terrorist operation conducted in Tunisia in March 2015 against a group of…
• 1400 CEOpoczno foundedOpoczno ([ɔˈpɔt͡ʂnɔ] ) is a town in south-central Poland, seat of Opoczno County in the Łódź Voivodeship.…
• 1921 CEOppau explosionThe Oppau explosion occurred on September 21, 1921, when approximately 4,500 tonnes of a mixture of ammonium…
• 1509 CEOr Qapi (fortress) builtOr Qapi Fortress is a ruined fort located near the settlement of Perekop on the Perekop isthmus connecting…
• 2025 CEOr Tor Kor Market shootingOn 28 July 2025, at 12:31 ICT (UTC+7), a mass shooting occurred at the Or Tor Kor Market (Thai: ตลาด อ.ต.ก.…
• 1113 CEOradea foundedOradea (UK:, US:, Romanian: [oˈrade̯a]; Hungarian: Nagyvárad [ˈnɒɟvaːrɒd]; German: Großwardein…
• 1703 CEOran ExpeditionThe Oran Expedition in 1707 was a military operation led by Moulay Ismail ibn Sharif in which he attempted to…
• 1854 CEOrange River ConventionThe Orange River Convention (sometimes also called the Bloemfontein Convention; Afrikaans…
• 1990 CEOrania foundedOrania (Afrikaans pronunciation: [uəˈrɑːnia]) is a white separatist South African town founded by Afrikaners.…
• 1941 CEOranienbaum BridgeheadThe Oranienbaum Bridgehead (Ораниенбаумский плацдарм in Russian) was an isolated portion of the Leningrad…
• 1893 CEOranjestad foundedOranjestad (Dutch pronunciation: [oːˈrɑɲəstɑt]; English: Orange Town) is a small town of 1,038 inhabitants…
• 1241 CEOrava Castle builtOrava Castle (Slovak: Oravský hrad, Hungarian: Árva vára) is a castle situated on a high rock above Orava…
• 1230 CEOravița foundedOravița (Romanian pronunciation: [oˈravit͡sa]; Hungarian: Oravicabánya; German: Orawitz; Czech: Oravice…
• 1999 CEOrderud caseThe Orderud case (Norwegian: Orderud-saken) was a triple murder that occurred in Sørum, Akershus, Norway, on…
• 1323 CEOreshek Fortress builtThe Oreshek Fortress (Russian: Крепость Орешек; Schlüsselburg Fortress, Russian: Шлиссельбургская крепость)…
• 1540 CEOrivirran saarto (fortress) builtOrivirran saarto is a ruin of a 16th-century fortress located in Savonranta, Finland. It is believed to be…
• 800 CEOrkhon inscriptions (monument) builtThe Orkhon inscriptions are bilingual texts in Middle Chinese and Old Turkic, the latter written in the Old…
• 2016 CEOrlando nightclub shootingOn June 12, 2016, 29-year-old Omar Mateen shot and killed 49 people and wounded 58 in a mass shooting at…
• 1983 CEOrly Airport attackThe Orly Airport attack was the 15 July 1983 bombing of a Turkish Airlines check-in counter at Orly Airport…
• 1300 CEOrlík Castle builtOrlík Castle (Czech: Zámek Orlík) is a château in Orlík nad Vltavou, in Písek District in the South Bohemian…
• 1337 CEOrsanmichele (church building) builtOrsanmichele, Or San Michele or Orsammichele (pronounced [orsammiˈkɛːle]; from the Tuscan contraction of Orto…
• 1856 CEOrtaköy Mosque builtOrtaköy Mosque (Turkish: Ortaköy Camii), formally the Büyük Mecidiye Camii (Turkish: Büyük Mecidiye Camii…
• 26000 BCEOruanui eruptionThe Oruanui eruption (also known as the Kawakawa eruption or Kawakawa/Oruanui event) of Taupō Volcano in New…
• 1101 CEOrval Abbey builtOrval Abbey (Abbaye Notre-Dame d'Orval) is a Cistercian monastery founded in 1132 in the Gaume region of…
• 1290 CEOrvieto Cathedral builtOrvieto Cathedral (Italian: Duomo di Orvieto; Cattedrale di Santa Maria Assunta) is a large 14th-century…
• 1997 CEOsaka Auto MesseThe Osaka Auto Messe (大阪オートメッセ) is an annual auto show that is held at Intex Osaka in Osaka, Japan since…
• 1931 CEOsaka Castle Park settledOsaka Castle Park (大阪城公園, Osaka-Jō-Kōen) is a public urban park and historical site situated at Osaka-Jō in…
• 1583 CEOsaka Castle builtOsaka Castle (大坂城 or 大阪城, Ōsaka-jō) is a Japanese castle in Chūō-ku, Osaka, Japan. The castle is one of…
• 1889 CEOsaka foundedOsaka (Japanese: 大阪市, Hepburn: Ōsaka-shi; pronounced [òó.sá.ká.ɕì, óó.-]; commonly just 大阪, Ōsaka [òó.sá.ká…
• 2008 CEOsaka movie theater fireOn 1 October 2008 at around 3 a.m., an adult video arcade in Osaka was set on fire deliberately. As a result…
• 1990 CEOsh riots1990 Osh riots (Kyrgyz: Ош окуясы; Uzbek: Oʻsh voqeasi, Ўш воқеаси; Russian: Ошская резня) were an ethnic…
• 1479 CEOshi Castle builtOshi Castle (忍城, Oshi-jō) is a Japanese castle located in Gyōda, Saitama Prefecture, Japan. During the Edo…
• 1301 CEOsiou Gregoriou monastery builtThe Holy Monastery of Saint Gregory (Greek: Ιερά Μονή Οσίου Γρηγορίου), also known as Gregoriou Monastery…
• 1697 CEOslo Cathedral builtOslo Cathedral (Norwegian: Oslo domkirke) — formerly Our Savior's Church (Norwegian: Vår Frelsers kirke) — is…
• 1048 CEOslo foundedOslo is the capital and most populous city of Norway. It constitutes both a county and a municipality. The…
• 1570 CEOsman Shah Mosque builtThe Osman Shah Mosque (Greek: Τέμενος Οσμάν Σαχ), also known as the Kursum Mosque (Κουρσούμ Τζαμί, from…
• 1976 CEOsmussaar earthquakeThe Osmussaar earthquake occurred on 25 October 1976 near the north tip of Osmussaar, an island close to the…
• 780 CEOsnabrück foundedOsnabrück (German: [ɔsnaˈbʁʏk]; Westphalian: Ossenbrügge; archaic English: Osnaburg) is a city in Lower…
• 2014 CEOso mudslideA major landslide occurred 4 miles (6.4 km) east of Oso, Washington, United States, on March 22, 2014, at…
• 1882 CEOsowiec Fortress builtOsowiec Fortress (Polish: Twierdza Osowiec; Russian: Крепость Осовец, romanized: Krepost' Osovets) is a…
• 700 BCEOstia foundedOstia Antica (lit. 'Ancient Ostia') is the modern name given to the ancient Roman city of Ostia. It became…
• 1267 CEOstrava foundedOstrava (Czech pronunciation: [ˈostrava]; Polish: Ostrawa Polish pronunciation: [ɔsˈtra.va]; German: Ostrau)…
• 2019 CEOstrava hospital attackThe Ostrava hospital shooting was a mass shooting that occurred on 10 December 2019 at the Ostrava University…
• 1600 CEOstrožac Castle builtOstrožac Castle (Bosnian) is a castle located in Bosnia and Herzegovina in the Una-Sana Canton on the…
• 1659 CEOsu Castle builtOsu Castle (also known as Fort Christiansborg or Christiansborg Castle) is a castle located in Osu, a…
• 2014 CEOtakon VegasOtakon Vegas ( OH-tə-kon) was a three-day anime convention held during January at the Planet Hollywood Resort…
• 1219 CEOtrar CatastropheThe Otrar Catastrophe was a siege that took place between December 1219 and February 1220 during the Mongol…
• 2012 CEOttawa ComicconThe Ottawa Comiccon is a fan convention with a focus on comics, sci-fi, horror, anime, and games. It is a…
• 1855 CEOttawa foundedOttawa (; Canadian French: [ɔtawɑ] ) is the capital city of Canada. It is located in the southeastern portion…
• 764 CEOttobeuren Abbey builtOttobeuren is a Benedictine abbey, located in Ottobeuren, near Memmingen in the Bavarian Allgäu, Germany. For…
• 1354 CEOttoman Wars in EuropeA series of military conflicts between the Ottoman Empire and various European states took place from the…
• 1585 CEOttoman expedition against the DruzeThe 1585 Ottoman expedition against the Druze, also called the 1585 Ottoman invasion of the Chouf, was an…
• 1481 CEOttoman invasion of OtrantoIn the summer of 1480, the Ottoman Empire invaded southern Italy, and laid siege to Otranto (Kingdom of…
• 1730 CEOttoman–Persian War of 1730–1735The Ottoman–Persian War of 1730–1735 was a conflict between the forces of Safavid Iran and those of the…
• 1050 CEOuagadougou foundedOuagadougou or Wagadugu (Mossi: Waogdgo, pronounced [ˈwɔɣədəɣʊ]; Dyula: Wagadugu; French: Ouagadougou…
• 1998 CEOued Bouaicha massacreThe Oued Bouaïcha massacre took place about 150 miles (240 km) south of Algiers, near Djelfa, on March 26…
• 1160 CEOurense Cathedral builtThe Ourense Cathedral (Catedral de Ourense or Catedral do San Martiño) is a Roman Catholic church located in…
• 1953 CEOutpost HarryOutpost Harry was a remote Korean War outpost located on a tiny hilltop in what was commonly referred to as…
• 1942 CEOutpost SnipeThe Defence of Outpost Snipe in Egypt was part of the Second Battle of El Alamein, part of the Western Desert…
• 1988 CEOuvéa cave hostage takingThe Ouvéa cave hostage taking occurred from 22 April 1988 to 5 May 1988 on the island of Ouvéa, New…
• 2022 CEOwo church attackOn 5 June 2022, a mass shooting and bomb attack occurred at a Catholic church in the city of Owo in Ondo…
• 2021 CEOxford High School shootingOn November 30, 2021, a school shooting occurred at Oxford High School in Oxford Township, Michigan, United…
• 1000 CEOxford foundedOxford is a cathedral city and non-metropolitan district in Oxfordshire, England, of which it is the county…
• 1314 CEOzbek Han Mosque builtThe Ozbek Han Mosque (Crimean Tatar: Özbek Han Camisi) is a mosque in Staryi Krym, Crimea. The Ozbek Han…
• 1996 CEOzone Disco Club fireThe Ozone Disco fire in Quezon City, Philippines, occurred on March 18, 1996, leaving 162 people dead. It is…
• 1370 CEOțelu Roșu foundedOțelu Roșu (Romanian pronunciation: [oˌt͡selu ˈroʃu], lit. (the) “Red Steel”; formerly Ferdinand; Hungarian…

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• 1988 CEPEPCON disasterOn May 4, 1988, a fire followed by several explosions occurred at the Pacific Engineering and Production…
• 1705 CEPact of GenoaThe Pact of Genoa was a military and political alliance formed in 1705 between the Kingdom of England and…
• 1982 CEPadkhwab-e Shana massacreThe Padkhwab-e Shana massacre or Pad Khwab-e Shanah massacre was a war crime perpetrated by the Soviet Army…
• 1960 CEPadrão dos Descobrimentos (monument) builtThe Monument of the Discoveries (Portuguese: Padrão dos Descobrimentos, Portuguese pronunciation: [pɐˈðɾɐ̃w…
• 1182 BCEPadua foundedPadua ( PAD-ew-ə) is a city and comune (municipality) in Veneto, northern Italy, and the capital of the…
• 1944 CEPadule di Fucecchio massacreThe Padule di Fucecchio massacre (Italian: Eccidio del Padule di Fucecchio) was the murder of at least 174…
• 599 BCEPaestum foundedPaestum ( PEST-əm, US also PEE-stəm, Latin: [ˈpae̯stũː]) was a major ancient Greek city on the coast of the…
• 1913 CEPakhlavan Mahmoud Mausoleum builtThe Pahlavon Mahmud complex, Pahlavon Mahmud mausoleum or Polvon ota mausoleum is a memorial monument in…
• 1992 CEPaklenik massacreThe Paklenik massacre is the massacre of 48 Bosniaks by the Army of the Republika Srpska in the Rogatica…
• 1893 CEPaknam IncidentThe Paknam Incident was a military engagement fought during the Franco-Siamese crisis in July 1893. While…
• 1991 CEPakrac clashThe Pakrac clash, known in Croatia as the Battle of Pakrac (Croatian: Bitka za Pakrac), was a bloodless…
• 850 CEPalace Leone da Perego builtPalazzo Leone da Perego is a historical building in Legnano. It was rebuilt in 1898 preserving some…
• 1752 CEPalace of Caserta builtThe Royal Palace of Caserta (Italian: Reggia di Caserta [ˈrɛddʒa di kaˈzɛrta, - kaˈsɛrta]; Neapolitan: Reggia…
• 1100 CEPalace of Coudenberg builtThe Palace of Coudenberg (French: Palais du Coudenberg; Dutch: Koudenbergpaleis) was a royal residence…