- For information on the number, see 1990 (number).
- For the Temptations album, see 1990 (Temptations album)
- "MCMXC" redirects here; for the Enigma album, see MCMXC a.D..
- January 3 - Former leader of Panama Manuel Noriega surrenders to American forces.
- January 7 - The Leaning Tower of Pisa is closed to the public due to safety concerns.
- January 9 - Lt Gen Bazilio Olara Okello, the man who led the coup against Dr Apolo Milton Obote's government, dies in Ormduruman Hospital in Khartoum, Sudan.
- January 10 - Time Warner is formed from the merger of Time Inc. and Warner Communications Inc.
- January 11 - Massive (200,000) demonstration in favor of Lithuanian independence.
- January 13 - Douglas Wilder becomes the first elected African American governor as he takes office in Richmond, Virginia.
- January 15 - Thousands storm the Stasi HQ in Berlin in an attempt to view their records.
- January 18:
- January 22 - Robert Tappan Morris, Jr. is convicted of releasing the 1988 Internet worm.
- January 25
- January 25-26 - Burns' Day storm rages over northwestern Europe - 97 dead
- January 27 - City of Tiraspol in the Moldavian SSR declares brief independence
- January 29 - The trial of the former skipper of the Exxon Valdez, Joseph Hazelwood, begins in Anchorage, Alaska. He is accused of negligence that resulted in America's worst oil spill.
- January 31 - The first McDonald's opens in Moscow, USSR.
- February 2 - Apartheid: In South Africa President F.W. de Klerk allows the African National Congress to legally function again and promises to set Nelson Mandela free.
- February 7 - Collapse of the Soviet Union: The Central Committee of the Soviet Communist Party agrees to give up its monopoly of power
- February 10 - South African President F.W. de Klerk announces that Nelson Mandela would be released the next day.
- February 11
- February 13 - German reunification: An agreement is reached for a two-stage plan to reunite Germany
- February 15 - The United Kingdom and Argentina restore diplomatic links after 8 years. The UK had broken off links in response to Argentina's invasion of the Falkland Islands, a British Dependent Territory
- February 26
- February 27 - Exxon Valdez oil spill: Exxon and its shipping company are indicted on five criminal counts.
- March 1
- March 6 - An SR-71 sets a US transcontinental speed record of 1 hour 8 minutes 17 seconds, on what is publicized as its last official flight.
- March 9
- March 9 - Newfoundland and Labrador Premier Clyde Wells confirms he will rescind Newfoundland's approval of the Meech Lake Accord, effectively killing the Accord
- March 10 - 18 months after seizing power in a coup, Prosper Avril is ousted in Haiti
- March 11
- March 15
- Gulf War: Iraqis hang British journalist Farzad Bazoft for spying. Daphne Parish, a British nurse, is sentenced to 15 years' imprisonment as an accomplice
- Mikhail Gorbachev is elected as the first executive president of the Soviet Union
- The Soviet Union announces that Lithuania's declaration of independence is invalid
- March 18
- 12 paintings, collectively worth $100 million, are stolen by two thieves posing as police officers from the Isabella Stewart Gardner Museum in Boston, Massachusetts. This is the largest art theft in US history and the paintings (as of 2005) have not been recovered
- East Germany holds first free elections since 1932
- March 18 - Thieves loot Isabella Steward Gardner Museum in Boston, Massachusetts, stealing paintings and treasures worth estimated $200 million (not recovered as of 2005)
- March 20 - Ferdinand Marcos's widow, Imelda Marcos, goes on trial for bribery, embezzlement, and racketeering
- March 21
- March 23 - Gerald Bull assassinated in Brussels
- March 24- The government of Australian prime minister Bob Hawke is re-elected for a 4th term.
- March 25 - In New York City, a fire due to arson at an illegal social club called "Happy Land" kills 87
- March 27 - Propaganda: The United States begins broadcasting TV Martí to Cuba
- March 27 - Namibia becomes a state independent of South Africa
- March 28 - President George H. W. Bush presents Jesse Owens with the Congressional Gold Medal.
- March 31 - London anti-Poll Tax Riots in Trafalgar Square. Incident subsequently known as "The Second Battle of Trafalgar"
- April 7
- April 13 - The Soviet Union apologizes for the Katyn Massacre
- April 15 - Food poisoning kills 450 guests of an engagement party in Uttar Pradesh
- April 24
- May 2 - In London, England, man brandishing a knife robs courier Nicholas Lane of bearer bonds worth £292 million - the largest mugging to date.
- May 15
- Portrait of Doctor Gachet by Vincent van Gogh is sold for a record $82.5 million.
- May 19 - British agriculture Minister John Gummer feeds a hamburger to his 5-year-old daughter to counter rumours about the spread of Mad cow disease and its transmission to humans
- May 20 - The first post- Communist presidential and parliamentary elections are held in Romania
- May 22
- May 29 - Rhode Island celebrates its bicentennial statehood.
- June 1 - U.S. President George H. W. Bush and Soviet Union leader Mikhail Gorbachev sign a treaty to end chemical weapon production and to start destroying each of their nation's stockpiles
- June 12 - The parliament of the Russian Federation formally declares its sovereignty (see Russia Day)
- June 20 - British Chancellor John Major proposes a new European currency which would circulate alongside existing national currencies (now knowen as the euro).
- June 22 - Underwater volcano Mount Didicas erupts in the Philippines
- July 2 - Stampede in a pedestrian tunnel leading to Mecca - 1426 pilgrims dead
- July 8
- July 12 - Square Co., Ltd. releases Final Fantasy in North America.
- July 15 - Tamil Tigers kill 168 Muslims in Colombo, Sri Lanka
- July 16 - In the Philippines, an earthquake measuring 7.7 on the Richter Scale kills over 1600
- July 25 - The Serbian Democratic Party declares sovereignty of the Serbs in Croatia
- July 27
- The parliament building and a government television house in Port-of-Spain, Trinidad and Tobago are stormed by the Jamaat al Muslimeen in a Coup d'état attempt which lasts five days. Approximately 26 to 30 people are killed and several wounded (including then Prime Minister, A.N.R. Robinson, who was shot in the leg).
- Belarus declares its sovereignty; a key step toward independence from the USSR.
- July 28 - Alberto Fujimori becomes president of Peru
- July 30 - IRA car bomb kills British MP Ian Gow, a staunch unionist.
- August 2 - Gulf War: Iraq invades Kuwait, eventually leading to the Gulf War.
- August 3 - The highest temperature recorded in the UK until 2003 - 37.1°C (98.8°F) at Cheltenham in Gloucestershire
- August 6 - Gulf War: The United Nations Security Council orders a global trade embargo against Iraq in response to Iraq's invasion of Kuwait.
- August 7 - John Cain Resigns as VIC premier over a series of financial scandals and is replaced by Joan Kirner (10th)
- August 7 - At 12:34:56 (both AM and PM) the time and date by British reckoning was 12:34:56 7/8/90 i.e. 1234567890.
- August 19 - Leonard Bernstein conducts his final concert, ending with Ludwig van Beethoven's Symphony No. 7 performed by the Boston Symphony Orchestra.
- August 27- Blues musician Stevie Ray Vaughan dies in a helicopter crash along with 4 others following a concert near East Troy, Wisconsin.
- September 2 - Transnistria declares its independence from the Moldavian SSR; however, the declaration is not recognized by any government.
- September 11 - President George H. W. Bush delivers a nationally televised speech in which he threatens the use of force to remove Iraqi soldiers from Kuwait, which Iraq had recently invaded.
- September 12 - The two German states and the Four Powers sign the Treaty on the Final Settlement With Respect to Germany in Moscow, paving the way for German re-unification.
- October 3 - German re-unification, East Germany becomes part of the Federal Republic of Germany.
- October 5 - After one hundred and fifty years, ten months and two days (Friday, January 3, 1840 - Friday, October 5, 1990), The Herald broadsheet newspaper in Melbourne, Australia is published for the last time as a separate newspaper. Founded in 1840 as The Port Phillip Herald, it is merged with its morning tabloid sister paper The Sun News-Pictorial and the first issue of the new Herald Sun, described by owner Rupert Murdoch as "The world's first 24-hour newspaper", with morning and afternoon editions, is published on the 8th
- October 8 - Israeli-Palestinian Conflict: In Jerusalem, Israeli police kill 17 Palestinians and wound over 100 near the Dome of the Rock mosque on the Temple Mount
- October 13 - Lebanese Civil War: Syrian military forces invade and occupy Mount Lebanon, ousting General Michel Aoun's government. This effectively consolidates Syria's 14 year occupation of Lebanese soil.
- October 15 - Soviet Union leader Mikhail Gorbachev is awarded the Nobel Peace Prize for his efforts to lessen Cold War tensions and reform his nation.
- October 27 - Supreme Soviet of Kyrgyzstan choses Askar Akayev as republic's first president
- October 27 - New Zealand general election returns National with record number of seats - 67; Labour 29, NewLabour 1
- November 1 - Mary Robinson defeats odds-on favourite Brian Lenihan to become the first woman President of Ireland.
- November 1 - The Australian domestic avation market is deregulated.
- November 5 - Rabbi Meir Kahane, founder of the far-right Kach movement, is shot dead after a speech at a New York City hotel and Reynir Ver Jónsson borned.
- November 8 - Mary Robinson becomes the first female president of the Republic of Ireland.
- November 11 - Gulf War: The U.N. Security Council passes Resolution 678, giving Iraq until Tuesday, January 15, 1991 to withdraw its forces from Kuwait
- November 12
- November 13 - The first known web page is written.
- November 14 - Germany and Poland sign a treaty confirming the border at the Oder-Neisse line.
- November 15 - Space Shuttle program: Space Shuttle Atlantis launches with flight STS-38.
- November 18 - Andrei Tjikatilo is arrested on suspicion of serial murder and rape
- November 21 - The Super Famicom (aka Super Nintendo) is released in Japan
- November 22 - Margaret Thatcher resigns as the Prime Minister of the United Kingdom.
- November 25 - Lech Wałęsa and Stanisław Tymiński win the 1st round of first presidential elections in Poland, see: December 9
- November 27 - The UK Conservative Party chooses John Major to succeed Margaret Thatcher as Prime Minister of the United Kingdom.
- November 29 - Gulf War: The United Nations Security Council passes UN Security Council Resolution 678, authorizing military intervention in Iraq if that nation did not withdraw its forces from Kuwait and free all foreign hostages by Tuesday, January 15, 1991.
- November 29 - Treasurer Paul Keating announces that Australia is experiencing an economic recession.
- December 1
- Channel Tunnel workers from the United Kingdom and France meet 40 meters beneath the English Channel seabed, establishing the first ground connection between the United Kingdom and the mainland of Europe since the last ice age
- The Los Angeles, California radio station KROQ opens their first annual Acoustic Christmas live concert.
- December 2 - A coalition led by Chancellor Helmut Kohl wins the first free all-German elections since 1932
- December 3
- At Detroit Metropolitan Airport, a McDonnell Douglas DC-9 carrying Northwest Airlines Flight 1482 collides with a Boeing 727 carrying Northwest Airlines Flight 299 on the runway, killing 8 passengers and 4 crewmembers aboard flight 1482
- Mary Robinson is elected the first female President of Ireland.
- December 6 - Saddam Hussein releases the Western hostages
- December 9
- December 16 - Jean-Bertrand Aristide is elected president of Haiti, ending three decades of military rule.
- December 31 - Russian Garry Kasparov holds his title by winning the World Chess Championship match against his countryman Anatoly Karpov.
- January 7 - Liam Aiken, American actor
- January 30 - Jake Thomas, American actor
- February 11 - Q'Orianka Kilcher, German-born actress
- February 13 - Erdini Qoigyijabu, eleventh Panchen Lama
- February 23 - Christian Copelin, American actor
- February 28 - Anna Muzychuk, Ukrainian chess player
- March 8 - Abigail and Brittany Hensel, American conjoined twins
- March 23 - Princess Eugenie of York
- March 24 - Keisha Castle-Hughes, Australian-born actress
- April 9 - Kristen Stewart, American actress
- April 10 - Alex Pettyfer, British actor
- April 15 - Emma Watson, British actress
- May 1 - Caitlin Stasey, Australian actress
- May 2 - Kay Panabaker, American actress
- May 16 - Thomas Sangster, English actor
- July 24 - Daveigh Chase, American actress
- September 5 - Shane McCrorie, King of Broadmeadows
- October 18 - Carly Schroeder, American actress
- October 22 - Jonathan Lipnicki, American actor
- November 7 - Marisa Siketa, Australian actress
- November 27 - Shane Haboucha, American actor
- November 30 - Magnus Carlsen, Norwegian chess player
- December 17 - Ashley Edner, American actress
- December 20 - Joanna Noelle Levesque, American singer
- January 2 - Alan Hale Jr., American actor (b. 1918)
- January 4 - Doc Edgerton, American electrical engineering (b. 1903)
- January 6 - Pavel Alekseyevich Cherenkov, Russian physicist, Nobel Prize laureate (b. 1904)
- January 9 - Spud Chandler, baseball player (b. 1907)
- February 17 - Erik Rhodes, American actor (b. 1906)
- March 13 - Karl Münchinger, German conductor (b. 1915)
- March 20 - Lev Yashin, Russian footballer (b.1929)
- April 15 - Greta Garbo, Swedish actress (b.1905)
- April 17 - Ralph Abernathy, American civil rights leader (b. 1926)
- May 16 - Sammy Davis Jr., American actor, dancer, and singer (b. 1925)
- May 16 - Jim Henson, American puppeteer (b. 1936)
- June 3 - Stiv Bators, American singer (The Dead Boys) (b. 1949)
- June 22 - Ilya Frank, Russian physicist, Nobel Prize laureate (b. 1908)
- July 7 - Bill Cullen, American game show host (b. 1920)
- July 18 - Yun Po Sun, President of South Korea (b. 1897)
- July 22 - Manuel Puig, Argentinian writer (b. 1932)
- August 27 - Stevie Ray Vaughan, American guitarist (b. 1954)
- September 16 - Len Hutton, English cricketer (b. 1916)
- September 26 - Alberto Moravia, Italian novelist (b. 1907)
- September 30 - Patrick White, Australian writer, Nobel Prize laureate (b. 1912)
- October 13 - Le Duc Tho, Vietnamese general and politician, recipient of the Nobel Peace Prize (b. 1911)
- October 14 - Leonard Bernstein, American composer and conductor (b. 1918)
- November 17 - Robert Hofstadter, American physicist, Nobel Prize laureate (b. 1915)
- November 23 - Roald Dahl, English writer (b. 1916)
- December 2 - Aaron Copland, American composer (b. 1900)
- December 14 - Friedrich Dürrenmatt, Swiss writer (b. 1921)
- Physics - Jerome Isaac Friedman, Henry Way Kendall, and Richard Edward Taylor
- Chemistry - Elias James Corey
- Medicine - Joseph E. Murray, E. Donnall Thomas
- Literature - Octavio Paz
- Peace - Mikhail Sergeyevich Gorbachev
- Alice Tepper Marlin, Bernard Lédéa Ouedraogo, Felicia Langer and ATCC (Asociación de Trabajadores Campesinos del Carare)
For a brief while in early 1990, Romania had a civil war in the aftermath of the Romanian Revolution of 1989, the opposition was for Nicolae Ceauşescu and the Communist regime, and those for the new regime.
- New Revised Standard Version of the Bible is published in the United States.
- Metropolitan Aleksy of Leningrad elected Russian Orthodox Patriarch of Moscow and all Russia.
- First Anglican female priests in the United Kingdom are ordained at St. Anne's Cathedral, Belfast, Northern Ireland.
- Robert Runcie announces resignation as Archbishop of Canterbury. George Carey succeeds him.
- Channel 7 + 10 networks go into recivership (Aus)
- Homosexual Acts between Consenting adults decriminalized in Queensland
- Beginnings of Trance musicaf:1990
ar:1990 ast:1990 bg:1990 be:1990 bs:1990 ca:1990 cs:1990 cy:1990 da:1990 de:1990 et:1990 el:1990 als:1990 es:1990 eo:1990 eu:1990 fo:1990 fr:1990 fy:1990 gl:1990 ko:1990년 hr:1990 io:1990 id:1990 ia:1990 is:1990 it:1990 he:1990 kn:೧೯೯೦ ka:1990 csb:1990 kw:1990 la:1990 lt:1990 lb:1990 hu:1990 mk:1990 mi:1990 nl:1990 ja:1990年 no:1990 nn:1990 os:1990 pl:1990 pt:1990 ro:1990 ru:1990 sq:1990 scn:1990 simple:1990 sk:1990 sl:1990 sr:1990 fi:1990 sv:1990 tl:1990 tt:1990 th:พ.ศ. 2533 tpi:1990 tr:1990 uk:1990 wa:1990 zh:1990年