1157

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.