On This Day — 1 May

2026

After a ransomware attack by the group ShinyHunters, the education platform Canvas operated by private company Instructure, goes offline, affecting thousands of educational institutions.

2026 Canvas data breach

2024

The 2024 Loblaw boycott, a Canadian boycott against retail corporation and grocer Loblaw Companies, begins.

Loblaw Companies

2019

Naxalite attack in Gadchiroli district of India: Sixteen army soldiers, including a driver, killed in an IED blast. Naxals targeted an anti-Naxal operations team.

Naxalism

2019

Naruhito ascends to the throne of Japan succeeding his father Akihito, beginning the Reiwa period.

Naruhito

2018

Syrian civil war: The Syrian Democratic Forces (SDF) resumes the Deir ez-Zor campaign in order to clear the remnants of the Islamic State of Iraq and the Levant (ISIL) from the Iraq–Syria border.

Syrian civil war

2011

Pope John Paul II is beatified by his successor, Pope Benedict XVI.

Pope John Paul II

2010

Faisal Shahzad attempts to detonate a car bomb in Times Square, but the bomb fails to go off.

Faisal Shahzad

2009

Same-sex marriage is legalized in Sweden.

Same-sex marriage in Sweden

2004

Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, and Slovenia join the European Union, celebrated at the residence of the Irish President in Dublin.

Cyprus

2003

Invasion of Iraq: In what becomes known as the "Mission Accomplished" speech, on board the USS Abraham Lincoln (off the coast of California), U.S. President George W. Bush declares that "major combat operations in Iraq have ended".

2003 invasion of Iraq

1999

The body of British climber George Mallory is found on Mount Everest, 75 years after his disappearance in 1924.

George Mallory

1997

The Labour Party wins the 1997 General Election and Tony Blair is elected as Prime Minister.

1997 United Kingdom general election

1994

Three-time Formula One champion Ayrton Senna is killed in an accident during the San Marino Grand Prix.

Formula One

1993

Sri Lankan President Ranasinghe Premadasa is assassinated in Colombo in a suicide bombing carried out by the Liberation Tigers of Tamil Eelam.

President of Sri Lanka

1991

Angolan Civil War: The MPLA and UNITA agree to the Bicesse Accords, which are formally signed on May 31 in Lisbon.

Angolan Civil War

1982

Operation Black Buck: The Royal Air Force attacks the Argentine Air Force during the Falklands War.

Operation Black Buck

1978

Japan's Naomi Uemura, travelling by dog sled, becomes the first person to reach the North Pole alone.

Naomi Uemura

1975

The Särkänniemi Amusement Park opens in Tampere, Finland.

Särkänniemi

1971

Amtrak (the National Railroad Passenger Corporation) takes over operation of U.S. passenger rail service.

Amtrak

1970

Vietnam War: Protests erupt in response to U.S. and South Vietnamese forces attacking Vietnamese communists in a Cambodian Campaign.

Vietnam War

1961

The Prime Minister of Cuba, Fidel Castro, proclaims Cuba a socialist nation and abolishes elections.

Prime Minister of Cuba

1960

Cold War: U-2 incident: Francis Gary Powers, in a Lockheed U-2 spyplane, is shot down over the Sverdlovsk Oblast, Soviet Union, sparking a diplomatic crisis.

Cold War

1957

A Vickers VC.1 Viking crashes while attempting to return to Blackbushe Airport in Yateley, killing 34.

Vickers VC.1 Viking

1956

The polio vaccine developed by Jonas Salk is made available to the public.

Polio vaccine

1947

Portella della Ginestra massacre against May Day celebrations in Sicily by the bandit and separatist leader Salvatore Giuliano where 11 persons are killed and 33 wounded.

Portella della Ginestra massacre

1946

Start of three-year Pilbara strike of Indigenous Australians.

Pilbara strike

1945

World War II: German radio broadcasts news of Adolf Hitler's death, falsely stating that he has "fallen at his command post in the Reich Chancellery fighting to the last breath against Bolshevism and for Germany". The Soviet flag is raised over the Reich Chancellery, by order of Stalin.

World War II

1945

World War II: Up to 2,500 people die in a mass suicide in Demmin following the advance of the Red Army.

Mass suicide in Demmin

1931

The Empire State Building is dedicated in New York City.

Empire State Building

1930

"Pluto" is officially proposed for the name of the newly discovered dwarf planet by Vesto Slipher in the Lowell Observatory Observation Circular. The name quickly catches on.

Pluto

1929

The 7.2 Mw  Kopet Dag earthquake shakes the Iran–Turkmenistan border region with a maximum Mercalli intensity of IX (Violent), killing up to 3,800 and injuring 1,121.

1929 Kopet Dag earthquake

1925

The All-China Federation of Trade Unions is officially founded. Today it is the largest trade union in the world, with 134 million members.

All-China Federation of Trade Unions

1921

The Jaffa riots commence.

Jaffa riots (May 1921)

1919

German troops enter Munich to suppress the Bavarian Soviet Republic.

Munich

1915

RMS Lusitania departs from New York City on her 202nd, and final, crossing of the North Atlantic. Six days later, the ship is torpedoed off the coast of Ireland with the loss of 1,198 lives.

RMS Lusitania

1900

The Scofield Mine disaster kills over 200 men in Scofield, Utah in what is to date the fifth-worst mining accident in United States history.

Scofield Mine disaster

1898

Spanish–American War: Battle of Manila Bay: The Asiatic Squadron of the United States Navy destroys the Pacific Squadron of the Spanish Navy after a seven-hour battle. Spain loses all seven of its ships, and 381 Spanish sailors die. There are no American vessel losses or combat deaths.

Spanish–American War

1896

Naser al-Din, Shah of Iran, is assassinated in Shah Abdol-Azim Shrine by Mirza Reza Kermani, a follower of Jamal al-Din al-Afghani.

Naser al-Din Shah Qajar

1894

Coxey's Army, the first significant American protest march, arrives in Washington, D.C.

Coxey's Army

1886

Rallies are held throughout the United States demanding the eight-hour work day, culminating in the Haymarket affair in Chicago, in commemoration of which May 1 is celebrated as International Workers' Day in many countries.

Haymarket affair

1885

The original Chicago Board of Trade Building opens for business.

Chicago Board of Trade Building

1866

The Memphis Race Riots begin. Over three days, 46 blacks and two whites were killed. Reports of the atrocities influenced passage of the Fourteenth Amendment to the United States Constitution.

Memphis massacre of 1866

1865

The Empire of Brazil, Argentina, and Uruguay sign the Treaty of the Triple Alliance.

Empire of Brazil

1863

American Civil War: The Battle of Chancellorsville between Robert E. Lee's Confederate Army of Northern Virginia and the Union Army of the Potomac under Joseph Hooker begins.

American Civil War

1863

American Civil War: During the Vicksburg campaign, Union forces under Ulysses S. Grant win the Battle of Port Gibson and establish a firm presence on the east side of the Mississippi River.

Vicksburg campaign

1851

Queen Victoria opens The Great Exhibition at The Crystal Palace in London.

Queen Victoria

1846

The few remaining Mormons left in Nauvoo, Illinois, formally dedicate the Nauvoo Temple.

Mormons

1844

Hong Kong Police Force, the world's second modern police force and Asia's first, is established.

Hong Kong Police Force

1840

The Penny Black, the first official adhesive postage stamp, is issued in the United Kingdom.

Penny Black

1820

Execution of the Cato Street Conspirators, who plotted to kill the British Cabinet and Prime Minister Lord Liverpool.

Cato Street Conspiracy

1807

The Slave Trade Act 1807 takes effect, abolishing the slave trade within the British Empire.

Slave Trade Act 1807

1753

Publication of Species Plantarum by Linnaeus, and the formal start date of plant taxonomy adopted by the International Code of Botanical Nomenclature.

Carl Linnaeus

1707

The Act of Union joining England and Scotland to form the Kingdom of Great Britain takes effect.

Acts of Union 1707

1669

Henry Morgan's raid on Lake Maracaibo: the Spanish Armada de Barlovento is defeated by an English Privateer fleet led by Captain Henry Morgan.

Henry Morgan's raid on Lake Maracaibo

1492

The Edict of Expulsion is officially proclaimed in Castile, requiring all Jewish residents to leave within three months.

Alhambra Decree

1486

Christopher Columbus presents his plans for discovering a western route to the Indies to the Spanish Queen Isabella I of Castile.

Christopher Columbus

1455

Scottish Royal forces loyal to King James II defeat a rebel army of the Black Douglases in the battle of Arkinholm.

Kingdom of Scotland

1328

Wars of Scottish Independence end: By the Treaty of Edinburgh–Northampton, England recognises Scotland as an independent state.

Wars of Scottish Independence

1169

Norman mercenaries land at Bannow Bay in Leinster, marking the beginning of the Norman invasion of Ireland.

Normans

880

The Nea Ekklesia is inaugurated in Constantinople, setting the model for all later cross-in-square Orthodox churches.

Nea Ekklesia

418

A synod in Carthage condemns Pelagianism.

Councils of Carthage

305

Diocletian and Maximian retire from the office of Roman emperor.

Diocletian