Papal Inquisition established
The Pope hands the hunt for heretics to special judges
In 1231 Pope Gregory IX's bull Excommunicamus made the prosecution of heresy a matter for church courts, and from 1233 he appointed Dominican inquisitors, first of all against the Cathars of southern France. This was the start of the papal Inquisition.
Wikipedia (English) · 13th century
Meanwhile around the world (±25 years)
Eastern Europe & Russia
- 1223 Battle of the Kalka River — 8 years earlier
- 1237–1240 Mongol invasion of Rus' — 6 years later
- 1240 Batu Khan takes Kiev — 9 years later
- c. 1242 The Golden Horde is founded — 11 years later
Asia
- 1206 Temüjin proclaimed Genghis Khan — 25 years earlier
- 1206 Founding of the Delhi Sultanate — 25 years earlier
- 1219 The Mongols invade Khwarazm — 12 years earlier
- c. 1251 The Tripitaka Koreana — 20 years later
Oceania
- c. 1250 The moai of Easter Island — 19 years later
Alive at the time
- Kublai Khan (aged 16)
- Alexander Nevsky (aged 10)
- Frederick II (aged 37)
- Rumi (aged 24)
- Saint Louis (Louis IX) (aged 17)
- Sundiata Keita (aged 14)
- Rudolf I (aged 13)
- Thomas Aquinas (aged 6)
- Fibonacci (aged 61)
- Yuri II of Vladimir (aged 42)