July 26

Byzantine Emperor Nikephoros I is killed in battle against Bulgarian forces led by Khan Krum.

Byzantine Emperor Nikephoros I was killed in battle against the forces of Bulgarian Khan Krum during a campaign deep into Bulgarian territory, a defeat so severe that Krum reportedly had the emperor's skull fashioned into a ceremonial drinking cup, an event that shocked contemporary Byzantine chroniclers.

Ferdinand of Aragon and Isabella of Castile marry, a union that later leads to the unification of Spain.

The marriage of Ferdinand of Aragon and Isabella of Castile united two of medieval Spain's most powerful kingdoms under a joint monarchy. Their combined reign later financed Columbus's voyages, completed the Reconquista by conquering Granada, and laid the political foundation for the unified Spanish state.

The world's first recorded women's cricket match is played in Surrey, England.

Two amateur women's cricket teams played what is considered the earliest documented match of its kind in Surrey, England, at a time when organized sport for women was extremely rare. The match reflects the surprisingly early, if limited, presence of women's participation in English cricket history.

The U.S. Post Office is established, with Benjamin Franklin appointed its first Postmaster General.

The Second Continental Congress established a centralized postal system for the American colonies, appointing Benjamin Franklin, who had previously served as a British colonial postmaster, as the first Postmaster General. The service laid the foundation for the modern United States Postal Service.

New York becomes the 11th state to ratify the U.S. Constitution.

New York became the eleventh state to ratify the newly drafted U.S. Constitution, doing so narrowly after intense debate between Federalist and Anti-Federalist factions, including influential essays later compiled as the Federalist Papers. Ratification allowed New York to join the new federal union alongside the other founding states.

The Bureau of Investigation, later renamed the FBI, is founded in the United States.

The U.S. Department of Justice established the Bureau of Investigation, a small force of special agents tasked with investigating federal crimes. The agency was later renamed the Federal Bureau of Investigation in 1935 and grew into the United States' principal federal law enforcement and domestic intelligence agency.

Fidel Castro leads an armed attack on the Moncada Barracks in Cuba, an event later commemorated as the start of the Cuban Revolution.

A group of Cuban revolutionaries led by Fidel Castro launched a poorly planned and ultimately unsuccessful assault on the Moncada army barracks in Santiago de Cuba. Though the attack failed and many participants were killed or imprisoned, the date became a rallying symbol for Castro's later successful revolution against the Batista government.

Egyptian President Gamal Abdel Nasser nationalizes the Suez Canal, precipitating the Suez Crisis.

Egyptian President Gamal Abdel Nasser announced the nationalization of the Suez Canal, previously operated by a British and French-controlled company, intending to use its revenues to fund the Aswan Dam project. The move triggered the Suez Crisis, a brief war and major geopolitical rupture between Egypt and the former colonial powers.

The first geosynchronous communications satellite, Syncom 2, is successfully launched.

The United States successfully launched Syncom 2, the first satellite placed into a geosynchronous orbit, meaning it remained roughly above the same point on Earth's surface. The technology proved transformative for global telecommunications, enabling continuous satellite coverage for television and communication signals.

Apollo 15 launches from Kennedy Space Center on a mission featuring the first use of a Lunar Roving Vehicle.

Astronauts David Scott, Alfred Worden, and James Irwin launched aboard Apollo 15, a mission notable for introducing the battery-powered Lunar Roving Vehicle, which allowed astronauts to travel much greater distances across the Moon's surface than earlier missions had permitted on foot.