An EF4 tornado strikes the Oklahoma-Kansas state line, killing 21 people and injuring over 100.

A hand grenade thrown by Vladimir Arutinian lands about 65 feet (20 metres) from U.S. President George W. Bush while he is giving a speech to a crowd in Tbilisi, Georgia, but it malfunctions and does not detonate.

The May 2003 tornado outbreak sequence takes place.

F.B.I. agent Robert Hanssen is given a life sentence without the possibility of parole for selling United States secrets to Moscow for $1.4 million in cash and diamonds.

A 7.3 M_w earthquake strikes Iran's Khorasan Province, killing 1,567, injuring over 2,300, leaving 50,000 homeless, and damaging or destroying over 15,000 homes.

A "rogue storm" near the summit of Mount Everest kills eight climbers, making this the deadliest day in the mountain's history. Among the dead are experienced climbers Rob Hall and Scott Fischer, both of whom were leading paid expeditions to the summit.

Nelson Mandela is inaugurated as South Africa's first black president.

In Thailand, a fire at the Kader Toy Factory kills 188 workers.

François Mitterrand wins the presidential election and becomes the first Socialist President of France in the French Fifth Republic.

The Federated States of Micronesia become self-governing.

Vietnam War: The Battle of Dong Ap Bia begins with an assault on Hill 937. It will ultimately become known as Hamburger Hill.

The nuclear submarine {{USS|Triton|SSRN-586|6}} completes Operation Sandblast, the first underwater circumnavigation of the earth.

Bill Haley & His Comets release "Rock Around the Clock", the first rock and roll record to reach number one on the ''Billboard'' charts.

First successful launch of an American V-2 rocket at White Sands Proving Ground.

World War II: The Thai Phayap Army invades the Shan States during the Burma Campaign.

World War II: Rudolf Hess parachutes into Scotland to try to negotiate a peace deal between the United Kingdom and Nazi Germany.

World War II: The House of Commons in London is damaged by the Luftwaffe in an air raid.

World War II: Invasion of Iceland by the United Kingdom.

World War II: Winston Churchill is appointed Prime Minister of the United Kingdom.

World War II: Germany invades Belgium, the Netherlands, and Luxembourg.

World War II: The first German bombs of the war fall on England at Chilham and Petham, in Kent.

Censorship: In Germany, the Nazis stage massive public book burnings.

J. Edgar Hoover is appointed the Director of the United States' Federal Bureau of Investigation, and remains so until his death in 1972.

The United States annex the Kingman Reef.

Mother's Day is observed for the first time in the United States, in Grafton, West Virginia.

The Supreme Court of the United States rules in ''Nix v. Hedden'' that a tomato is a vegetable, not a fruit, under the Tariff Act of 1883.

Romania declares itself independent from the Ottoman Empire following the Senate adoption of Mihail Kogălniceanu's Declaration of Independence. This act is recognized on March 26, 1881 after the end of the Romanian War of Independence.

Victoria Woodhull becomes the first woman nominated for President of the United States.

The First Transcontinental Railroad, linking the eastern and western United States, is completed at Promontory Summit, Utah (not Promontory Point, Utah) with the golden spike.

American Civil War: In Kentucky, Union soldiers ambush and mortally wound Confederate raider William Quantrill, who lingers until his death on June 6.

American Civil War: Jefferson Davis is captured by Union troops near Irwinville, Georgia.

American Civil War: Colonel Emory Upton leads a 10-regiment "Attack-in-depth" assault against the Confederate works at The Battle of Spotsylvania, which, though ultimately unsuccessful, would provide the idea for the massive assault against the Bloody Angle on May 12. Upton is slightly wounded but is immediately promoted to Brigadier general.

American Civil War: Confederate General Stonewall Jackson dies eight days after he is accidentally shot by his own troops.

Indian Mutiny: In India, the first war of Independence begins. Sepoys revolt against their commanding officers at Meerut.

Panic of 1837: New York City banks fail, and unemployment reaches record levels.

The desecration of the grave of the viceroy of southern Vietnam Le Van Duyet by Emperor Minh Mang provokes his adopted son to start a revolt.

The National Gallery in London opens to the public.

First Barbary War: The Barbary pirates of Tripoli declare war on the United States of America.

First Coalition: Napoleon I of France wins a decisive victory against Austrian forces at Lodi bridge over the Adda River in Italy. The Austrians lose some 2,000 men.

American Revolutionary War: Representatives from the Thirteen Colonies begin the Second Continental Congress in Philadelphia.

American Revolutionary War: Fort Ticonderoga is captured by a small Colonial militia led by Ethan Allen and Colonel Benedict Arnold.

Louis XVI becomes King of France.

John Wilkes is imprisoned for writing an article for ''The North Briton'' severely criticizing King George III. This action provokes rioting in London.

England, with troops under the command of Admiral William Penn and General Robert Venables, annexes Jamaica from Spain.

Jacques Cartier visits Newfoundland.

Christopher Columbus visits the Cayman Islands and names them ''Las Tortugas'' after the numerous turtles there.

Amerigo Vespucci allegedly leaves Cádiz for his first voyage to the New World.

Scottish nobles recognize the authority of Edward I of England.

Siege of Jerusalem: Titus, son of emperor Vespasian, opens a full-scale assault on Jerusalem and attacks the city's Third Wall to the northwest.