Codex Gigas, the Devil's Bible
The largest medieval manuscript, with a portrait of the Devil

The giant manuscript weighs about 75 kg, and one page shows a full-length portrait of the Devil. Legend says a monk condemned to be walled up wrote it in a single night with the Devil's help; in reality it took decades.
Wikipedia (Russian) · Wikipedia (English) · 13th century
Meanwhile around the world (±25 years)
Eastern Europe & Russia
- 1223 Battle of the Kalka River — 6 years earlier
- 1237–1240 Mongol invasion of Rus' — 8 years later
- 1240 Batu Khan takes Kiev — 11 years later
- c. 1242 The Golden Horde is founded — 13 years later
Asia
- 1206 Temüjin proclaimed Genghis Khan — 23 years earlier
- 1206 Founding of the Delhi Sultanate — 23 years earlier
- 1219 The Mongols invade Khwarazm — 10 years earlier
- c. 1251 The Tripitaka Koreana — 22 years later
Oceania
- c. 1250 The moai of Easter Island — 21 years later
Alive at the time
- Kublai Khan (aged 14)
- Alexander Nevsky (aged 8)
- Frederick II (aged 35)
- Rumi (aged 22)
- Saint Louis (Louis IX) (aged 15)
- Sundiata Keita (aged 12)
- Rudolf I (aged 11)
- Thomas Aquinas (aged 4)
- Fibonacci (aged 59)
- Yuri II of Vladimir (aged 40)