589 - Reccared summons the Third Council of Toledo
1450 - Jack Cade's Rebellion: Kentishmen revolt against King Henry VI.
1541 - Hernando de Soto reaches the Mississippi River and names it Río de Espíritu Santo.
1794 - Branded a traitor during the Reign of Terror by revolutionists, French chemist Antoine Lavoisier, who was also a tax collector with the Ferme Générale, is tried, convicted, and guillotined all on one day in Paris.
1821 - Greek War of Independence: The Greeks defeat the Turks in Gravia.
1846 - Mexican-American War: The Battle of Palo Alto – Zachary Taylor defeats a Mexican force north of the Rio Grande in the first major battle of the war.
1861 - American Civil War: Richmond, Virginia is named the capital of the Confederate States of America.
1886 - Pharmacist John Styth Pemberton invents a carbonated beverage that would later be named "Coca-Cola".
1898 - The first games of the Italian Football League are played.
1899 - The Irish Literary Theatre in Dublin opens.
1902 - In Martinique, Mount Pelée erupts, destroying the town of Saint-Pierre and killing over 30,000 people. Only a handful of residents survive the blast.
1919 - Edward George Honey first proposes the idea of a moment of silence to commemorate The Armistice of World War I, which later results in the creation of Remembrance Day.
1933 - Mohandas Gandhi begins a 21-day fast in protest against British oppression in India.
1942 - World War II: The Battle of the Coral Sea comes to an end with Japanese Imperial Navy aircraft carrier aircraft attacking and sinking the United States Navy aircraft carrier USS Lexington. The battle marks the first time in the naval history that two enemy fleets fight without visual contact between warring ships.
1942 - World War II: Gunners of the Ceylon Garrison Artillery on Horsburgh Island in the Cocos Islands rebel in the Cocos Islands Mutiny. Their mutiny is crushed and three of them are executed, the only British Commonwealth soldiers to be executed for mutiny during the Second World War.
1945 - Hundreds of Algerian civilians are killed by French Army soldiers in the Sétif massacre.
1945 - Combat in Europe ends in World War II: V-E Day. German forces agree to an unconditional surrender.
1945 - End of the Prague uprising, today still celebrated as a national holiday in the Czech Republic.
1946 - The Estonian school girls Aili Jõgi and Ageeda Paavel blow up the Soviet memorial that preceded the Bronze Soldier in Tallinn.
1967 - The Philippine province of Davao is split into three: Davao del Norte, Davao del Sur, and Davao Oriental.
1970 - The Hard Hat riot occurs in the Wall Street area of New York City as blue-collar construction workers clash with anti-war demonstrators protesting the Vietnam War.
1972 - Vietnam War – U.S. President Richard M. Nixon announces his order to place mines in major North Vietnamese ports in order to stem the flow of weapons and other goods to that nation.
1973 - A 71-day standoff between federal authorities and the American Indian Movement members occupying the Pine Ridge Reservation at Wounded Knee, South Dakota ends with the surrender of the militants.
1976 - The rollercoaster Revolution (roller coaster), the first steel coaster with a vertical flip, opens at Six Flags Magic Mountain
1984 - The Soviet Union announces that it will boycott the 1984 Summer Olympics in Los Angeles, California.
1984 - Cpl. Denis Lortie enters the Quebec National Assembly and opens fire, killing three and wounding 13. René Jalbert, sergeant-at-arms of the assembly, succeeds in calming him, for which he will later receive the Cross of Valour.
1987 - The Loughgall ambush: The SAS kill 8 IRA members and 1 civilian, in Loughgall, Northern Ireland.
1988 - A fire at Illinois Bell's Hinsdale Central Office triggers an extended 1AESS outage once considered the 'worst telecommunications disaster in US telephone industry history' is still the worst to occur on Mother's Day.