1157
Year 1157 was a common year starting on Tuesday of the Julian calendar.
Events
- January 12–March 16 – Caliph Al-Muqtafi successfully defends Baghdad against the coalition forces of Sultan Muhammad of Hamadan, and Atabeg Qutb-adin of Mosul.
- Albert I of Brandenburg begins his ruthless program to pacify the Slavic region.
- June 11 – Albert I of Brandenburg, also called The Bear, becomes the founder of the Margraviate of Brandenburg, Germany and the first Margrave.
- July – Henry II launches a campaign against Owain Gwynedd in north Wales. Although Owain defeats him at the Battle of Ewloe he eventually submits to Henry and pays homage.
- August 12 – The 1157 Hama earthquake takes place after a year of foreshocks. Its name is taken from the city of Hama, in west-central Syria, where the most casualties are sustained.
- August 21 – Sancho III and Ferdinand II, the sons of King Alfonso VII of Castile, divide his kingdom between them upon his death.
- October 23 – Battle of Grathe Heath: A civil war in Denmark ends with the death of King Sweyn III. Valdemar I of Denmark becomes king of all Denmark, and restores and rebuilds the country.
- Henry II of England grants special trading privileges to the Hansa merchants of Cologne in London who lend him money at interest.
- Henry II of England grants a charter to the merchants of Lincoln.
- Nur ad-Din Zengi besieges the Knights Hospitaller in the crusader fortress of Banyas, routs a relief army led by King Baldwin III of Jerusalem, and takes Grand Master Bertrand de Blanquefort prisoner.