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Events

July 8 or August 21 - Jin–Song Wars - Battle of Yancheng: Song dynasty general Yue Fei defeats an army led by Jin dynasty general Wuzhu.
September 30 - A magnitude 7.7 earthquake strikes the Caucasus mountains in the Seljuk Empire, causing great devastation and killing 300,000 people.
Europe
January 25 - Godfrey II, Count of Louvain becomes Duke of Lower Lorraine.
April 8 - Second Council of the Lateran: Roger II of Sicily is excommunicated by Pope Innocent II.
April 9 - The Treaty of Durham is signed, between King Stephen of England and David I of Scotland.
May - Representatives of Polvese Island formally submit the island to the city of Perugia, pledging military support, fiscal obligations, and an annual tribute of tench.
July 22 - Pope Innocent II, invading the Kingdom of Sicily, is ambushed at Galluccio and taken prisoner.
July 25
* Treaty of Mignano: Pope Innocent II proclaims Roger II of Sicily as King of Sicily, Duke of Apulia and Prince of Capua.
* Battle of Ourique: The independence of Portugal from the Kingdom of León is declared after the Almoravids, led by Ali ibn Yusuf, are defeated by Prince Afonso Henriques. He then becomes Afonso I, King of Portugal, after calling the first assembly of the Estates-General of Portugal at Lamego, where he is given the Crown from the Bishop of Bragança, to confirm the independence.
By topic

King's School, Pontefract, in England is founded.
Religion
April - Second Council of the Lateran: The Anacletus schism is settled, and priestly celibacy is made mandatory within the Catholic Church.
November - Alberic of Ostia, papal legate to Outremer, convenes a legatine council in the cathedral of Antioch to examine the conduct of the Latin patriarch. The council is also attended by the Armenian Catholicos Gregory III and marks a symbolic beginning for Armenian-Latin ecclesiastic high-level contacts.
Births
June 16 - Emperor Konoe of Japan
Agnes II - abbess and artist
Conon of Naso, Basilian abbot
Deaths
January 25 - Godfrey I, Count of Louvain and Duke of Lower Lorraine
February 18 - Prince Yaropolk II of Kiev
October 20 - Henry X, Duke of Bavaria
December - Roger of Salisbury, English bishop
Empress Xing of China