Browse Historical Events by Month: What Happened in October?

The Battle of Lepanto takes place, with the Holy League defeating the Ottoman Empire's navy in a significant naval battle.

The Spanish army captures Lisbon, effectively uniting the crowns of Portugal and Spain under Philip II.

The Gregorian calendar, decreed by Pope Gregory XIII, becomes effective in all the Catholic countries of Europe with the day after Thursday October 4, 1582 becoming Friday, 15 October 1582. The Spanish and Portuguese colonies followed somewhat later because of delay in communication. The Gregorian calendar is now widely used around the world. With the exception of Ethiopia, Nepal, Iran and Afghanistan, the Gregorian calendar is now the world's universal civil calendar, old style calendars remaining in use in religious or traditional contexts. More

Toyotomi Hideyoshi's forces emerge victorious in the Battle of Myeongnyang against the Japanese invasions of Korea.

The Treaty of Vervins is signed, ending the war between Spain and France.

1599, October - The Battle of Sellenberk takes place, marking a significant conflict during the Long War between the Ottoman Empire and the Habsburg Monarchy.

The Treaty of Weissenburg is signed, ending the War of the Jülich Succession between Spain and the Dutch Republic.

The Battle of Sekigahara takes place in Japan, leading to Tokugawa Ieyasu's rise to power and the establishment of the Tokugawa Shogunate.

Tycho Brahe, Danish astronomer, dies under mysterious circumstances.

Dutch navigator and merchant Willem Janszoon becomes the first recorded European to set foot on Australian soil.

Supernova Kepler's Star becomes visible, leading to Johannes Kepler's study of its movement.

The Battle of Kircholm occurs between the Polish-Lithuanian Commonwealth and Sweden.

The Dutch East India Company (VOC) is established to facilitate colonial trade.

Fire destroys most of the Palace of Whitehall in London.

Fire destroys most of the Palace of Whitehall in London.

English explorer Henry Hudson reaches the river that now bears his name during his search for the Northwest Passage.

Italian astronomer Galileo Galilei demonstrates his newly built telescope to Venetian lawmakers.

The Italian scientist Galileo Galilei discovers the four largest moons of Jupiter, now known as the Galilean moons.

The new Russian Tsar, Michael Romanov, is elected, marking the beginning of the Romanov dynasty.

Dutch sea captain Dirk Hartog makes the second recorded landfall by a European on Australian soil.