September 28

Roman general Pompey is assassinated in Egypt on the orders of King Ptolemy XIII shortly after fleeing there.

Fleeing to Egypt after his defeat by Julius Caesar in Rome's civil war, the once-powerful general Pompey was murdered on the orders of the young Egyptian king shortly after coming ashore, a betrayal intended to curry favor with the victorious Caesar.

Duke Wenceslaus I of Bohemia is murdered by nobles including his own brother, who succeeds him.

Duke Wenceslaus I of Bohemia, later venerated as a Christian martyr and the "Good King Wenceslas" celebrated in a famous Christmas carol, was murdered by conspirators including his own brother Boleslaus, who subsequently seized the Bohemian throne for himself. Wenceslaus was posthumously canonized and became one of the patron saints of the Czech nation.

William the Conqueror lands in England, beginning the Norman conquest.

William, Duke of Normandy, landed his invasion force unopposed on the English coast at Pevensey, beginning the military campaign that culminated in his decisive victory over King Harold II at the Battle of Hastings just over two weeks later. The successful invasion fundamentally transformed English language, culture, and governance for centuries to come.

King James I of Aragon conquers Valencia from Moorish rule and proclaims himself king of Valencia.

King James I of Aragon completed the conquest of the Moorish-held city of Valencia after a lengthy siege supported by Christian forces from across the Iberian Peninsula, proclaiming himself king of the newly captured territory. The conquest significantly advanced the broader Christian Reconquista of Iberia and established a new Kingdom of Valencia that persisted for centuries.

Portuguese explorer Juan Rodriguez Cabrillo becomes the first European to reach present-day California.

Portuguese-born explorer Juan Rodriguez Cabrillo, sailing under the Spanish flag on an expedition seeking a mythical passage to Asia, became the first European to reach the coast of present-day California, landing near what is now San Diego Bay during his exploratory voyage along the Pacific coastline in search of trade opportunities and territorial claims.

The Congress of the Confederation votes to send the newly drafted U.S. Constitution to the state legislatures for ratification.

The Congress of the Confederation, governing under the Articles of Confederation, voted to formally transmit the newly drafted Constitution to the individual state legislatures for the ratification process that would ultimately establish the new federal government. Nine of the thirteen states needed to ratify the document before it could take effect, a threshold reached less than a year later.

Alexander Fleming discovers penicillin after noticing bacteria-killing mold in his laboratory.

Returning from vacation, bacteriologist Alexander Fleming noticed that a stray mold spore had contaminated one of his laboratory culture plates and was killing the surrounding staphylococcus bacteria. This accidental observation led to the discovery of penicillin, the first true antibiotic, a breakthrough that revolutionized the treatment of bacterial infections and saved countless lives in the decades that followed.

Nazi Germany and the Soviet Union agree to divide occupied Poland between them.

Following their coordinated invasion of Poland weeks earlier, Nazi Germany and the Soviet Union signed a treaty formally dividing the occupied country between them, cementing the territorial arrangement first outlined in the secret protocols of the earlier Molotov-Ribbentrop non-aggression pact. The agreement effectively erased Poland as an independent state for the remainder of the war.

The cruise ferry MS Estonia sinks in the Baltic Sea, killing 852 people.

The passenger and vehicle ferry MS Estonia sank in rough seas in the Baltic Sea after its bow door failed, killing 852 people in one of the deadliest peacetime maritime disasters in European history and prompting significant reforms to ferry safety design and regulations.

Hurricane Ian makes landfall in Florida as a Category 4 storm, causing widespread destruction and billions of dollars in damage.

Hurricane Ian made landfall on Florida's southwestern coast as a powerful Category 4 storm, causing catastrophic storm surge flooding and wind damage that resulted in well over a hundred deaths and tens of billions of dollars in damage across the state.