October 18

The Church of the Holy Sepulchre in Jerusalem is completely destroyed on the orders of Fatimid Caliph Al-Hakim.

On the orders of the unstable Fatimid Caliph Al-Hakim bi-Amr Allah, workers systematically demolished the Church of the Holy Sepulchre in Jerusalem, one of Christianity's holiest sites believed to mark the location of Jesus's crucifixion and burial, an act of religious persecution that later contributed to growing European hostility that helped spark the Crusades.

Danish forces under Cnut defeat the English at the Battle of Assandun.

Danish forces under the future King Cnut the Great decisively defeated English defenders led by King Edmund Ironside at the Battle of Assandun in Essex, a victory achieved partly through the treachery of an English commander who withdrew his forces mid-battle. The triumph led directly to Cnut's subsequent conquest and rule over England, establishing a short-lived North Sea empire spanning Denmark, Norway, and England.

A powerful earthquake devastates Basel, Switzerland, one of the most destructive quakes recorded north of the Alps.

A major earthquake, estimated at magnitude 6.6 to 7.1, struck the city of Basel and the surrounding region of Switzerland, causing widespread destruction of buildings, castles, and church structures, followed by fires that compounded the damage. The quake remains recognized as one of the most damaging earthquakes ever recorded in Central Europe, a region not typically associated with major seismic activity given its distance from active tectonic plate boundaries.

Spanish conquistador Hernando de Soto's forces destroy the fortified town of Mabila in present-day Alabama.

Spanish explorer Hernando de Soto's expedition, seeking gold and engaging in often brutal conflict with Indigenous peoples during its extensive trek through the American Southeast, destroyed the fortified town of Mabila after a fierce battle with Chief Tuscaloosa's forces, resulting in devastating losses on both sides.

The Treaty of Aix-la-Chapelle is signed, concluding the War of the Austrian Succession.

European powers signed the Treaty of Aix-la-Chapelle, concluding the sprawling War of the Austrian Succession that had drawn in most major European powers, largely restoring prewar territorial boundaries while leaving many of the underlying dynastic and territorial disputes unresolved for future conflicts.

Herman Melville's novel "Moby-Dick" is first published in London under the title "The Whale."

Herman Melville's now-classic novel about Captain Ahab's obsessive pursuit of a great white whale was first published in London under a different title than its later American edition, initially receiving mixed critical reception and only achieving its now-legendary literary reputation decades after Melville's death.

The United States completes its acquisition of Alaska from Russia, formally raising the American flag over the territory.

American officials formally took possession of Alaska from Russia in a ceremony at Sitka, completing the purchase negotiated by Secretary of State William Seward for $7.2 million, a transaction initially mocked by critics but later recognized as a remarkably valuable acquisition following subsequent gold and oil discoveries.

The British Broadcasting Company is established, laying groundwork for the modern BBC.

The British Broadcasting Company was formed by a consortium of radio equipment manufacturers to provide a national broadcasting service, later reorganized as a public corporation that became the BBC, establishing a model of public service broadcasting influential in many countries worldwide.

Space Shuttle Atlantis launches carrying the Galileo spacecraft on its mission to study Jupiter.

Space Shuttle Atlantis launched from Kennedy Space Center carrying the Galileo spacecraft, which used a powerful inertial upper-stage rocket booster released from the shuttle's cargo bay to begin its six-year journey to Jupiter via gravity-assist flybys of Venus and Earth. Galileo eventually became the first spacecraft to orbit the giant planet, studying its atmosphere, moons, and powerful magnetic field in unprecedented detail.

NASA astronauts Jessica Meir and Christina Koch conduct the first all-female spacewalk from the International Space Station.

NASA astronauts Jessica Meir and Christina Koch ventured outside the International Space Station together to replace a faulty power component, the first spacewalk conducted entirely by a team of women, a milestone that came decades after the first spacewalk due to historical limitations on spacesuit availability and astronaut selection.