1270

For broader historical context, see 1270s and 13th century.

Years: 1267 1268 1269 - 1270 - 1271 1272 1273
Decades: 1240s 1250s 1260s - 1270s - 1280s 1290s 1300s
Centuries: 12th century - 13th century - 14th century 1270 state leaders

Events

December - Crucial aspects of the philosophy of Averroism (itself based on Aristotle's works) are banned by the Catholic church in a condemnation enacted by papal authority at the University of Paris.
The Summa Theologiae, a work by Thomas Aquinas that is considered within the Roman Catholic Church to be the paramount expression of its theology, is completed (year uncertain).
Witelo translates Alhazen's 200-year-old treatise on optics, Kitab al-Manazir, from Arabic into Latin, bringing the work to European academic circles for the first time.
The Sanskrit fables known as the Panchatantra, dating from as early as 200 BCE, are translated into Latin from a Hebrew version by John of Capua.
Construction of the Old New Synagogue in Prague is completed.
The cathedral on the Rock of Cashel in Ireland is completed.

In Korea, the Sambyeolcho Rebellion begins against the Goryeo Dynasty, a puppet government of the Mongol Empire.
The ancient city of Ashkelon is captured from the crusader states and utterly destroyed by the Mamluk sultan Baibars, who goes so far as to fill in its important harbor, leaving the site desolate and the city never to be rebuilt.
The city of Tabriz, in present-day Iran, is made capital of the Mongol Ilkhanate empire (approximate date).
The independent state of Kutch is founded in present-day India.
A census of the Chinese city of Hangzhou establishes that some 186,330 families reside within it, not including visitors and soldiers. (Historian Jacques Gernet argues that this means a population of over 1 million inhabitants, making Hangzhou the most populous city in the world.)

Before August - King Louis IX of France launches the Eighth Crusade in an attempt to recapture the crusader states from the Mamluk sultan Baibars; the opening engagement is a siege of Tunis.
August 25 - King Louis IX of France dies while besieging the city of Tunis, possibly due to poor quality drinking water.
October 30 - The siege of Tunis and the Eighth Crusade end by an agreement between Charles I of Sicily (Louis IX's brother) and the sultan of Tunis.