1252
Year 1252 was a leap year starting on Monday of the Julian calendar.
Events
By place
Europe
- April 6 - Saint Peter of Verona is assassinated by Carino of Balsamo.
- May 15 - Pope Innocent IV issues the papal bull Ad exstirpanda, which authorizes the torture of heretics in the Medieval Inquisition. Torture quickly gains widespread usage across Catholic Europe.
- June 1 - Alfonso X is proclaimed king of Castile and León.
- July - The settlement of Stockholm in Sweden is founded, by Birger Jarl.
- December 25 - Christopher I of Denmark is crowned King of Denmark, in the Lund Cathedral.
- The Polish land of Lebus is incorporated into the German state of Brandenburg, marking the start of Brandenburg's expansion into previously Polish areas.
- The Lithuanian city of Klaipėda is founded by the Teutonic Knights.
- The town and monastery of Orval Abbey in Belgium burn to the ground; rebuilding takes 100 years.
- Thomas Aquinas travels to the University of Paris, to begin his studies there for a master's degree.
- In astronomy, work begins on the recording of the Alfonsine tables.
Asia
- The classic Japanese text Jikkunsho is completed.
- The Chinese era Chunyou ends.
- Mongol conquest of the Song dynasty: the Mongols take the westernmost province of the Song dynasty empire.