December 28 - Dennis Wilson, American musician (The Beach Boys) (b. 1944)
January 1 - The ARPANET officially changes to using the Internet Protocol, creating the Internet.
January 18 - The International Olympic Committee restores Jim Thorpe's Olympic medals to his family.
January 19 - Nazi war criminal Klaus Barbie is arrested in Bolivia.
January 19 - The Apple Lisa, the first commercial personal computer from Apple Inc. to have a graphical user interface and a computer mouse, is announced.
January 27 - Pilot shaft of the Seikan Tunnel, the world's longest subaqueous tunnel (53.85 km) between the Japanese islands of Honshū and Hokkaidō breaks through.
February 8 - The Melbourne dust storm hits Australia's second largest city. The result of the worst drought on record and a day of severe weather conditions, the 320m deep dust cloud envelops the city, turning day to night.
February 14 - United American Bank of Knoxville, Tennessee collapses. Its president, Jake Butcher is later convicted of fraud.
February 16 - The Ash Wednesday bushfires in Victoria and South Australia claim the lives of 75 people in Australia's worst ever fires.
February 18 - Thirteen people die and one is seriously injured in the Wah Mee Massacre in Seattle, Washington. It is said to be the largest robbery-motivated mass-murder in U.S. history.
February 23 - The Spanish Socialist government of Felipe González and Miguel Boyer nationalizes Rumasa, a holding of José María Ruiz Mateos.
February 23 - The United States Environmental Protection Agency announces its intent to buy out and evacuate the dioxin-contaminated community of Times Beach, Missouri.
February 24 - A special commission of the U.S. Congress releases a report that condemns the practice of Japanese internment during World War II.
February 28 - The final episode of M*A*S*H is broadcast in the USA, becoming the most watched television episode in history, with 106–125 million viewers in the U.S. (estimate varies by source).
March 8 - President Ronald Reagan calls the Soviet Union an "evil empire."
March 8 - The U.S. House Foreign Affairs Committee endorses a nuclear weapons freeze with the Soviet Union, a move denounced by President Ronald Reagan.
March 16 - Demolition of the radio tower Ismaning, the last radio tower in Germany built of wood.
March 23 - Strategic Defense Initiative: President Ronald Reagan makes his initial proposal to develop technology to intercept enemy missiles.
April 4 - Space Shuttle Challenger makes its maiden voyage into space (STS-6).
April 7 - During STS-6, astronauts Story Musgrave and Don Peterson perform the first space shuttle spacewalk.
April 13 - Harold Washington is elected as the first African-American mayor in Chicago's history.
April 18 - A suicide bomber destroys the United States embassy in Beirut, Lebanon, killing 63 people.
April 22 - The German magazine, Der Stern claims that Adolf Hitler's diaries were found in wreckage in East Germany.
April 25 - American schoolgirl Samantha Smith is invited to visit the Soviet Union by its leader Yuri Andropov after he read her letter in which she expressed fears about nuclear war.
April 25 - Pioneer 10 travels beyond Pluto's orbit.
May 1 - Greek composer Mikis Theodorakis is awarded the Lenin Peace Prize.
May 6 - The Hitler diaries are revealed as a hoax when experts examine the books and conclude that they are fake.
May 16 - Sudan People's Liberation Army/Movement rebels against the Sudanese government.
May 17 - U.S. Department of Energy declassifies documents showing world's largest mercury pollution event in Oak Ridge, Tennessee (ultimately found to be 4.2 million pounds), in response to Appalachian Observer's Freedom of Information Act request.
May 17 - Lebanon, Israel, and the United States sign an agreement on Israeli withdrawal from Lebanon.
May 18 - In Ireland, the government launches a crackdown, with the leading Dublin pirate Radio Nova being put off the air.
May 20 - First publications of the discovery of the HIV virus that causes AIDS in the journal Science by Luc Montagnier and Robert Gallo individually.
May 26 - A strong 7.7 magnitude earthquake strikes Japan, triggering a tsunami that kills at least 104 people, injures thousands. Many people go missing and thousands of buildings are destroyed.
June 13 - Pioneer 10 becomes the first man-made object to leave the solar system.
June 18 - Space Shuttle program: STS-7, Astronaut Sally Ride becomes the first American woman in space.
June 24 - Space Shuttle program: STS-7: Sally Ride, the first female American astronaut, returns to earth.
June 25 - India wins the final of the Cricket World Cup against the mighty West Indies at the MCC's Lord's Cricket Ground in London.
June 28 - The Mianus River Bridge collapses over the Mianus River in Connecticut, killing 3 drivers in their vehicles.
July 1 - A North Korean Ilyushin Il-62M jet en route to Conakry Airport in Guinea crashes into the Fouta Djall Mountains in Guinea-Bissau, killing all 23 people on board.
July 7 - Cold War: Samantha Smith, a U.S. schoolgirl, flies to the Soviet Union at the invitation of Secretary General Yuri Andropov.
July 11 - A Boeing 727 crashes into hilly terrain after a tail strike in Cuenca, Ecuador, claiming 119 lives.
July 16 - Sikorsky S-61 disaster: A helicopter crashes off the Isles of Scilly, causing 20 fatalities.
July 19 - The first three-dimensional reconstruction of a human head in a CT is published.
July 20 - The Israeli cabinet votes to withdraw troops from Beirut but to remain in southern Lebanon.
July 21 - The world's lowest temperature is recorded at Vostok Station, Antarctica at −89.2°C (−129°F).
July 22 - Martial law in Poland is officially revoked.
July 23 - The Sri Lankan Civil War begins with the killing of 13 Sri Lanka Army soldiers by the Liberation Tigers of Tamil Eelam. In the subsequent government-organised pogrom of Black July, about 1,000 Tamils are slaughtered, some 400,000 Tamils flee to neighbouring Tamil Nadu, India and many find refuge in Europe and Canada.
July 23 - Gimli Glider: Air Canada Flight 143 runs out of fuel and makes a deadstick landing at Gimli, Manitoba.
July 24 - George Brett batting for the Kansas City Royals against the New York Yankees, has a game-winning home run nullified in the "Pine Tar Incident".
July 25 - Black July: 37 Tamil political prisoners at the Welikada high security prison in Colombo are massacred by the fellow Sinhalese prisoners.
July 27 - Black July: 18 Tamil political prisoners at the Welikada high security prison in Colombo were massacred by the Sinhalese prisoners, the second such massacre in two days.
August 18 - Hurricane Alicia hits the Texas coast, killing 22 people and causing over USD $1 billion in damage (1983 dollars).
August 21 - Philippine opposition leader Benigno Aquino, Jr. is assassinated at the Manila International Airport (now renamed Ninoy Aquino International Airport).
August 26 - Flooding destroys most of the old town of Bilbao, Spain.
September 1 - Cold War: Korean Air Flight 007 is shot down by a Soviet Union jet fighter when the commercial aircraft enters Soviet airspace. All 269 on board are killed, including United States Congressmen Lawrence McDonald.
September 6 - The Soviet Union admits to shooting down Korean Air Flight KAL-007, stating that the pilots did not know it was a civilian aircraft when it violated Soviet airspace.
September 12 - A Wells Fargo depot in West Hartford, Connecticut, United States, is robbed of approximately US$7 million by Los Macheteros.
September 12 - The USSR vetoes a UN Security Council Resolution deploring the Soviet shooting down of a Korean civilian jetliner on September 1.
September 17 - Vanessa Williams becomes the first black Miss America.
September 23 - Gerrie Coetzee of South Africa becomes the first African boxing world heavyweight champion.
September 25 - Maze Prison escape: 38 republican prisoners, armed with 6 handguns, hijack a prison meals lorry and smash their way out of HMP Maze. It is the largest prison escape since WWII and in British history.
September 26 - Soviet military officer Stanislav Petrov averts a worldwide nuclear war.
September 26 - Australia II, the first non-American winner, wins the Americas Cup.
September 27 - Richard Stallman announces the GNU project to develop a free Unix-like operating system.
October 4 - Richard Noble sets a new land speed record of 633.468 mph (1,019 km/h), driving Thrust 2 at the Black Rock Desert of Nevada.
October 9 - Rangoon bombing: attempted assassination of South Korean President Chun Doo-hwan during an official visit to Rangoon, Burma. Chun survives but the blast kills 17 of his entourage, including four cabinet ministers, and injures 17 others. Four Burmese officials also die in the blast.
October 12 - Japan's former Prime Minister Tanaka Kakuei is found guilty of taking a $2 million bribe from Lockheed and is sentenced to 4 years in jail.
October 13 - Ameritech Mobile Communications (now AT&T) launched the first US cellular network in Chicago, Illinois.
October 17 - Grateful Dead played for their one and only appearance in Lake Placid, NY
October 19 - Maurice Bishop, Prime Minister of Grenada, is overthrown and executed in a military coup d'état led by Bernard Coard.
October 21 - The metre is defined at the seventeenth General Conference on Weights and Measures in terms of the speed of light as the distance light travels in a vacuum in 1/299,792,458 of a second.
October 22 - Two correctional officers are killed by inmates in Marion, Illinois. The incident inspired the Supermax model of prisons.
October 23 - Lebanon Civil War: The U.S. Marines barracks in Beirut is hit by a truck bomb, killing 241 U.S. Marines. A French army barracks in Lebanon is also hit that same morning, killing 58 troops.
October 25 - Operation Urgent Fury: The United States and its Caribbean allies invade Grenada, six days after Prime Minister Maurice Bishop and several of his supporters were executed in a coup d'état.
October 29 - Over 500,000 people demonstrate against cruise missiles in The Hague, The Netherlands.
October 30 - The first democratic elections in Argentina after seven years of military rule are held.
November 2 - U.S. President Ronald Reagan signs a bill creating Martin Luther King, Jr. Day.
November 5 - Byford Dolphin diving bell accident kills five and leaves one severely injured.
November 7 - 1983 United States Senate bombing: a bomb explodes inside the U.S. Capitol Building.
November 15 - Turkish Republic of Northern Cyprus is founded. Recognised only by Turkey
November 17 - The Zapatista Army of National Liberation is founded.
November 26 - Brinks Mat robbery: In London, 6,800 gold bars worth nearly £26 million are stolen from the Brinks Mat vault at Heathrow Airport.
November 27 - A Colombian Boeing 747 crashes near Madrid's Barajas Airport, killing 183.
November 29 - Soviet war in Afghanistan: The United Nations General Assembly passes United Nations Resolution 37/37, stating that Soviet Union forces should withdraw from Afghanistan.
December 5 - Dissolution of the Military Junta in Argentina.
December 5 - ICIMOD established and inaugurated with its headquarters in Kathmandu, Nepal, and legitimised through an Act of Parliament in Nepal in the same year.
December 7 - An Iberia Airlines Boeing 727 collides with an Aviaco DC-9 in dense fog while the two airliners are taxiing down the runway at Madrid Barajas International Airport, killing 93 people.
December 10 - Democracy is restored in Argentina with the assumption of President Raúl Alfonsín.
December 17 - The IRA bombs Harrods Department Store in London, killing six people.
December 19 - The original FIFA World Cup trophy, the Jules Rimet Trophy, is stolen from the headquarters of the Brazilian Football Confederation in Rio de Janeiro.
December 31 - The AT&T Bell System is broken up by the United States Government.