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Events

Emperor John II Komnenos recovers southwestern Anatolia from the Seljuk Turks and then hastens to the Balkans, where the Pechenegs are continuing their incursions. He transfers Byzantine troops to the Danube frontier at Paristrion.

Summer - Seljuk forces under Toghtekin make extensive raids into Galilee. King Baldwin II of Jerusalem, in reprisal, crosses the Jordan River with a Crusader army and ravages the countryside. He occupies and destroys a fortress that Toghtekin has built at Jerash.

March 2 - Petronilla of Lorraine becomes regent of Holland after her husband, Floris II dies. He is succeeded by his 6-year-old son Dirk VI.
A large rebellion takes place in Córdoba against the ruling Almoravid dynasty.

Summer - Sultan Mahmud II of the Seljuk Empire declares a Holy War on the Kingdom of Georgia. He sends an expedition under Ilghazi, the Artukid ruler of Mardin, to invade the country.
August 12 - Battle of Didgori: King David IV defeats the 300,000-strong Seljuk coalition forces at Mount Didgori.
The much larger Seljuk army is heavily defeated; Georgia is unified and independence is achieved from Muslim authority. King David IV lays siege and captures Tbilisi later in the year assigning it as his capital.

Emperor Emperor Huizong of Song sends an expedition to crush the rebellion at Hangzhou in China. The rebels are defeated and their leader Fang La is captured and executed.

Spring - Peter Abelard, a French theologian and philosopher, is condemned and charged with the heresy of Sabellius in a synod at Soissons. Abelard writes Sic et Non.
April 22 - Antipope Gregory VIII is arrested by papal troops at Sutri. He is taken to Rome and imprisoned in the Septizonium.
December 25 - The Praemonstratensian Order is formed, when a group of canons make solemn vows at Prémontré.
Henry I founds Reading Abbey in England. The Cluniac Order populates the abbey.
The third and largest church is completed at Cluny Abbey.
L'Aumône Abbey is founded by Count Theobald IV of Blois at Loir-et-Cher.