21 July 1899

People returning from anti–extradition bill protests in Hong Kong were attacked (pictured) by suspected triad members in Yuen Long, leaving 45 people injured.

Harry Potter and the Deathly Hallows, the final book in the popular Harry Potter series by J. K. Rowling, was released and sold 15 million copies in its first 24 hours, making it the fastest-selling book in history.

The Taiwanese military ordered the deportation of dozens of illegal immigrants from mainland China in sealed boat holds, causing 25 deaths due to suffocation.

Libyan forces carried out a raid at Sallum, sparking a four-day war with Egypt.

The Troubles: The Provisional Irish Republican Army detonated twenty-two bombs throughout Belfast, Northern Ireland.

Sirimavo Bandaranaike (pictured) was sworn in as prime minister of Ceylon, becoming the world's first democratically elected female head of government.

The inaugural International Mathematical Olympiad, the leading mathematical competition for pre-university students, began in Romania.

An earthquake registering 7.3 Mw struck the southern San Joaquin Valley in California, causing 12 deaths and an estimated $60 million in property damage.

After weeks of unrest, rioters lynched Bolivian president Gualberto Villarroel, desecrating and hanging his corpse in the streets of La Paz.

American high-school biology teacher John T. Scopes was found guilty of violating Tennessee's Butler Act which forbade teaching evolution in class.

World War I: An Imperial German Navy U-boat opened fire on a small convoy of barges and defending aircraft near the American town of Orleans, Massachusetts.

Much of central Pittsburgh, Pennsylvania, was burned and looted during the Great Railroad Strike of 1877.

Unrepresented labourers revolted and violently took over the government of the Republic of Florence (depicted), demanding that they be granted political office.

Louis III, Holy Roman Emperor, was captured and blinded during his attempt to restore Carolingian power over Italy by King Berengar I.

A large earthquake occurred near Crete, triggering a tsunami, and causing widespread destruction around the eastern Mediterranean region.

Pope Pontian began his pontificate, succeeding Urban I.

A Bangladesh Air Force Chengdu FT-7BGI crashes shortly after takeoff into Milestone School campus in Dhaka, Bangladesh, killing 35 people and injuring 173.

U.S. President Joe Biden announces he will no longer seek a second term and withdraws from the 2024 election, endorsing Vice President Kamala Harris as she launches her own presidential campaign.

The Barbenheimer phenomenon begins as two major motion pictures, Greta Gerwig's fantasy comedy Barbie and Christopher Nolan's epic biographical thriller Oppenheimer, are released in theaters on the same day and audiences, instead of creating a rivalry between the extremely dissimilar films, instead attend and praise both as an informal, surreal double feature.

Yuen Long attack or "721 incident" in Hong Kong. Triad members indiscriminately beat civilians returning from protests while police failed to take action.

NASA's Space Shuttle program ends with the landing of Space Shuttle Atlantis on mission STS-135 at NASA's Kennedy Space Center.

U.S. President Barack Obama signs the Dodd–Frank Wall Street Reform and Consumer Protection Act.

Ram Baran Yadav is declared the first President of Nepal.

At the conclusion of a fireworks display on Okura Beach in Akashi, Hyōgo, Japan, 11 people are killed and more than 120 are injured when a pedestrian footbridge connecting the beach to JR Asagiri Station becomes overcrowded and people leaving the event fall down in a domino effect.