Syrian civil war: Following the completion of the Afrin offensive, the Syrian Democratic Forces (SDF) initiate an insurgency against the Turkish occupation of the Afrin District.
Capitol Hill massacre: A gunman kills six people before taking his own life at a party in Seattle's Capitol Hill neighborhood.
Protesters demanding a new election in Belarus, following the rigged 2006 Belarusian presidential election, clash with riot police. Opposition leader Aleksander Kozulin is among several protesters arrested.
The European Union's Veterinarian Committee bans the export of British beef and its by-products as a result of mad cow disease (Bovine spongiform encephalopathy).
WikiWikiWeb, the world's first wiki, and part of the Portland Pattern Repository, is made public by Ward Cunningham.
The Candle demonstration in Bratislava is the first mass demonstration of the 1980s against the communist regime in Czechoslovakia.
The first fully functional Space Shuttle orbiter, Columbia, is delivered to the John F. Kennedy Space Center to be prepared for its first launch.
Faisal of Saudi Arabia is shot and killed by his nephew.
The Army of the Republic of Vietnam abandon an attempt to cut off the Ho Chi Minh trail in Laos.
Civil rights activists led by Martin Luther King Jr. successfully complete their four-day 50-mile (80 km) march from Selma to the capitol in Montgomery, Alabama.
Chain Island is sold by the State of California to Russell Gallaway III, a Sacramento businessman who plans to use it as a "hunting and fishing retreat", for $5,258.20 ($58,072 in 2025).
United States Customs seizes copies of Allen Ginsberg's poem "Howl" on obscenity grounds.
The European Economic Community is established with West Germany, France, Italy, Belgium, Netherlands and Luxembourg as the first members.
More than 92,000 kulaks are suddenly deported from the Baltic states to Siberia.
The first successful tornado forecast predicts that a tornado will strike Tinker Air Force Base, Oklahoma.
An explosion in a coal mine in Centralia, Illinois kills 111.
The Kingdom of Yugoslavia joins the Axis powers with the signing of the Tripartite Pact.
The Tomb of the Unknown Soldier is unveiled in Athens.
The Scottsboro Boys are arrested in Alabama and charged with rape.
On the anniversary of Greek Independence, Alexandros Papanastasiou proclaims the Second Hellenic Republic.
The Tetiev pogrom occurs in Ukraine, becoming the prototype of mass murder during the Holocaust.
The Belarusian People's Republic is established.
The Georgian Orthodox Church restores its autocephaly abolished by Imperial Russia in 1811.
The Greek multi-sport club Aris Thessaloniki is founded in Thessaloniki.
In New York City, the Triangle Shirtwaist Factory fire kills 146 garment workers.
Andrey Yushchinsky is murdered in Kiev, leading to the Beilis affair.
The Greek football club P.A.E. G.S. Diagoras is founded in the city of Rhodes.
Coxey's Army, the first significant American protest march, departs Massillon, Ohio for Washington, D.C.
Last issue of the Bulletin de la Fédération jurassienne, the first or one of the first anarchist newspapers.
American Civil War: In Virginia during the Siege of Petersburg, Confederate forces temporarily capture Fort Stedman from the Union before being repulsed.
New Zealand Legislative Council pass the first Militia Act constituting the New Zealand Army.
Greek War of Independence: Traditional date of the start of the Greek War of Independence. The war had actually begun on 23 February 1821 (Julian calendar).
Percy Bysshe Shelley is expelled from the University of Oxford for publishing the pamphlet The Necessity of Atheism.
The Swansea and Mumbles Railway, then known as the Oystermouth Railway, becomes the first passenger-carrying railway in the world.
The Treaty of Amiens is signed as a "Definitive Treaty of Peace" between France and the United Kingdom.
American Revolutionary War: American Patriots conduct a Raid on Tybee Island, primarily seeking to capture runaway slaves who sought refuge with British forces stationed there.
Daskalogiannis leads the people of Sfakia in the first Greek uprising against the Ottoman rule
Bach's chorale cantata "Wie schön leuchtet der Morgenstern, BWV 1", is first performed on the Feast of the Annunciation, coinciding with Palm Sunday.
A French fleet anchors nears Fife Ness as part of the planned French invasion of Britain.
Saturn's largest moon, Titan, is discovered by Christiaan Huygens.
Sir Walter Raleigh is granted a patent to colonize Virginia.
Jerome Savage takes out a sub-lease to start the Newington Butts Theatre outside London.
Hernán Cortés, entering province of Tabasco, defeats Tabascan Indians.
The Yongle Emperor of Ming China launches the first of his military campaigns against the Mongols, resulting in the fall of the Mongol khan Bunyashiri.
The Council of Pisa convenes, in an attempt to heal the Western Schism.
Robert the Bruce becomes King of Scots (Scotland).
Coronation of Robert of Courtenay as Emperor of the Latin Empire.
The Great German Pilgrimage is attacked on Good Friday by Beduin bandits, suffering heavy losses.
Fatimid caliph al-Hakim bi-Amr Allah assassinates the eunuch chief minister Barjawan and assumes control of the government.
Romanos Lekapenos seizes the Boukoleon Palace in Constantinople and becomes regent of the Byzantine emperor Constantine VII.
Theodosius III resigns the throne to the Byzantine Empire to enter a monastery, allowing Leo III to take the throne and begin the Isaurian dynasty.
Election of Pope Constantine following the death of Pope Sisinnius. He would be the last pope to visit Constantinople until 1967.
Italian city Venice is founded with the dedication of the first church, that of San Giacomo di Rialto on the islet of Rialto.
The Southern Yan capital of Guanggu falls to the Jin dynasty general Liu Yu, ending the Southern Yan dynasty.