1137

By place

Byzantine Empire

• Spring - Emperor John II leads a Byzantine expeditionary force into Cilicia. He defeats the Armenians under Prince Leo I, and captures the cities of Mersin, Tarsus, Adana and Mamistra. Leo retreats to the great fortifications of Anazarbus – where its garrison resists for 37 days. The Byzantine siege engines batter down its walls, and the city is forced to surrender. Leo escapes into the Taurus Mountains, while the Byzantine forces march southward into the plain of Antioch.
• August 29 - John II appears before the walls of Antioch, and encamps with the Byzantine army on the north bank of the Orontes River. For several days he besieges the city, Raymond of Poitiers is forced to surrender. He recognizes John as his suzerain and becomes with Joscelin II a vassal of the Byzantine Empire.

Levant

• March 25 - Bazwāj, a mamluk commander of Damascus, launches a military campaign against Tripoli, reaching Pilgrims' Mount. He defeats a Crusader army under Count Pons. Pons is forced to flee into the mountains where native Christians capture him. Later, he is handed over and instantly put to death by Bazwāj.
• Summer - Battle of Ba'rin: A Crusader force led by King Fulk, [King of Jerusalem|Fulk of Jerusalem] is scattered and defeated by Imad al-Din Zengi, Seljuk governor of Mosul. Fulk with a small bodyguard escapes into Montferrand Castle, which is surrounded and besieged by Zengi. After negotiations, Fulk is granted his freedom in exchange for the castle.

Europe

• April 9 - William X, duke of Aquitaine, dies while on a pilgrimage to Santiago de Compostela. On his deathbed, he expresses his wish to see King Louis VI of France in [the Middle Ages|France] as protector of his 15-year-old daughter Eleanor, and to find her a suitable husband.
• July 25 - Louis VI sends his 16-year-old son Louis Capet with an escort of 500 knights to Bordeaux, along with Abbot Suger in charge of the wedding arrangements. Louis and Eleanor are married in the Cathedral of Saint-André. France unites Aquitaine and its territories to the Pyrenees.
• August 1 - Louis VI dies of dysentery at Paris after a 29-year reign. He is succeeded by Louis Capet as King of France. During his accession the burgesses of Orléans and Poitiers revolt – who wish to organise communes.
• August 11 - Ramon Berenguer IV, count of Barcelona, is married to Princess Petronilla of Aragon – whose father, King Ramiro II of Aragon, seeks aid from Barcelona against King León and Castile|Alfonso VII] of Castile, abdicates the throne in favor of Ramon on November 13.
• October 30 - Battle of Rignano: Sergius VII, duke of Naples, is defeated by the Sicilian forces under King Roger II of Sicily. Sergius is killed and Roger establishes direct control over Naples – nominating his 17-year-old son Alfonso of Capua as the new duke.
• December 4 - Emperor Lothair III, [Holy Roman Emperor|Lothair III] dies at Breitenwang in Tyrol, while retreating from Italy after a mutiny among his troops. His son-in-law Henry X, duke of Bavaria, inherits the Duchy of Saxony.
• An Almoravid fleet of 37 ships attack the coasts of southern Italy, under Norman rule.

Britain

• Spring - King Stephen sails to Normandy to confront Geoffrey V and the Angevins, who are attacking the southern areas of Normandy. Although Stephen has some success, he is not able to recapture Normandy from Matilda, daughter and heiress of the late King Henry I.
• King Gruffudd ap Cynan of Gwynedd dies after a 56-year reign, having rebuilt Welsh power overturned earlier by Henry I. He is succeeded by his son Owain Gwynedd who together with his other brothers, Cadwaladr and Cadwallon, work to revive the power of Gwynedd in Wales.
• June 3 - A fire severely damages Rochester Cathedral, but it is soon rebuilt.
• June 4 - A fire destroys much of the city of York, including 39 churches and York Minster.
• June 27 - A fire severely damages the city of Bath.

Africa

• In the first commercial treaty between the Almohad Caliphate and a Christian power, the Republic of Genoa obtains trading rights in the port of North Africa.
• The Ethiopian Empire is established by Emperor Mara Takla Haymanot of the Zagwe Dynasty.

Asia

• In China during the Song Dynasty, a fire breaks out in the new capital of Hangzhou. The government suspends the requirement of rent payments, alms of 108,840 kg of rice are distributed to the poor, and items such as bamboo, planks and rush-matting are exempted from government taxation.