On this day: 22 May

Fourteenth recorded perihelion passage of Halley's Comet.

Henry Raspe is elected anti-king of the Kingdom of Germany in opposition to Conrad IV.

Serbian King Stefan Uroš I and the Republic of Venice sign a peace treaty.

Albrecht von Wallenstein and King Christian IV of Denmark signed the Treaty of Lübeck to end Danish intervention in the Thirty Years' War.

The Trevi Fountain (pictured) in Rome was officially inaugurated by Pope Clement XIII.

Sweden and Prussia sign the Treaty of Hamburg.

A magnitude-7.1 earthquake struck Constantinople and was followed by a tsunami that caused significant damage.

The Lewis and Clark Expedition officially begins as the Corps of Discovery departs from St. Charles, Missouri.

A grand jury indicts former Vice President of the United States Aaron Burr on a charge of treason.

On the second and last day of the Battle of Aspern-Essling (near Vienna, Austria), Napoleon I is defeated in a major battle for the first time in his career, and repelled by an enemy army for the first time in a decade.

SS Savannah leaves port at Savannah, Georgia, United States, on a voyage to become the first steamship to cross the Atlantic Ocean.

In Shiraz, Iran, the Báb declared himself to be a messenger of God to Mullá Husayn, leading to the foundation of Bábism, considered to be a precursor to the Baháʼí Faith.

The Associated Press is formed in New York City as a non-profit news cooperative.

Slavery is abolished in Martinique.

Abraham Lincoln was issued a patent for an invention to lift boats over obstacles in a river, making him the only U.S. president ever to hold a patent.

Senator Charles Sumner (pictured) was assaulted by Representative Preston Brooks in the United States Senate chamber in retaliation for a speech in which Sumner fiercely criticized slaveholders.

American Civil War: Union forces begin the Siege of Port Hudson which lasts 48 days, the longest siege in U.S. military history.

American Civil War: After ten weeks, the Union Army's Red River Campaign ends in failure.

Oliver Winchester founds the Winchester Repeating Arms.

Reconstruction Era: President Ulysses S. Grant signs the Amnesty Act into law, restoring full civil and political rights to all but about 500 Confederate sympathizers.

Sultan Abdul Hamid II established the Ullah millet, a separate millet for the Aromanians within the Ottoman Empire.

The Wright brothers are granted U.S. patent number 821,393 for their "Flying-Machine".

The Uruguayan Regional Workers' Federation declared a general strike in solidarity with trolley workers in Montevideo.

Chiang Kai-shek replaces the communists in Kuomintang China.[vague]

Germany and Italy signed the Pact of Steel, a military and political alliance.

Mexico enters the Second World War on the side of the Allies.

Joseph Stalin disbands the Comintern.

Cold War: The Truman Doctrine goes into effect, aiding Turkey and Greece.

Finnish President J. K. Paasikivi releases Yrjö Leino from his duties as interior minister after the Finnish parliament adopted a motion of censure of Leino with connection to his illegal handing over of nineteen people to the Soviet Union in 1945.

South Africa's government approves of racial separation in universities.

The most powerful earthquake ever recorded, registering approximately 9.5 Mw, struck near Valdivia, Chile, generating tsunamis that reached Hawaii and Japan.

U.S. President Lyndon B. Johnson launches his Great Society program.

Egypt closes the Straits of Tiran to Israeli shipping.

Apollo 10's Lunar Module flies within 8.4 nautical miles (16 km) of the Moon's surface.

Ceylon adopts a new constitution, becoming a republic and changing its name to Sri Lanka.

Location testing for Pac-Man, a Japanese arcade game that became an icon of 1980s popular culture, began in Shibuya, Tokyo.

First ever Rugby World Cup kicks off with New Zealand playing Italy at Eden Park in Auckland, New Zealand.

North and South Yemen are unified to create the Republic of Yemen.

Bosnia and Herzegovina, Croatia and Slovenia join the United Nations.

A worldwide trade embargo against Haiti goes into effect to punish its military rulers for not reinstating the country's ousted elected leader, Jean-Bertrand Aristide.

The Burmese military regime jails 71 supporters of Aung San Suu Kyi in a bid to block a pro-democracy meeting.

In Public Prosecutor v Taw Cheng Kong, the Court of Appeal of Singapore overruled a High Court decision in the only time a statute in Singapore had been ruled unconstitutional.

Inter Milan beat Bayern Munich 2–0 in the UEFA Champions League final in Madrid, Spain to become the first, and so far only, Italian team to win the historic treble (Serie A, Coppa Italia, Champions League).

Tokyo Skytree opens to the public. It is the tallest tower in the world (634 m), and the third tallest man-made structure on Earth after Merdeka 118 (680.5 m) and Burj Khalifa (829.8 m).

SpaceX COTS Demo Flight 2 launches a Dragon capsule on a Falcon 9 rocket in the first commercial flight to the International Space Station.

Prayut Chan-o-cha (pictured), the commander-in-chief of the Royal Thai Army, launched a coup d'état against the caretaker government following six months of political crisis.

The Republic of Ireland becomes the first nation in the world to utilise a public referendum to legalise gay marriage.

United States President Donald Trump visits the Church of the Holy Sepulchre in Jerusalem and becomes the first sitting U.S. president to visit the Western Wall.