1171
Year 1171 was a common year starting on Friday of the Julian calendar.Events
- Saladin abolishes the Fatimid Caliphate, restoring Sunni rule in Egypt.
- Manuel I Comnenus orders all the Venetians in the Byzantine Empire to be arrested, and their property confiscated.
- Rhys ap Gruffydd agrees to negotiate with Henry II of England.
- Construction of the Cathedral of San Sabino in Bari is completed.
- Serbian ruler Stefan Nemanja begins his sole reign.
- Alfonso II of Aragon conquers Caspe and Teruel.
- Henry II of England invades Ireland with the aid of the ousted King of Leinster, Diarmait Mac Murchada. As is usual at this time, Henry commandeers merchant ships as part of his invasion. Henry claims the ports of Dublin, Waterford, and Wexford for himself, and promises the Irish chieftains protection if they will acknowledge him as their overlord. This begins eight centuries of conflict between Ireland and England. Ascall mac Ragnaill, last Norse–Gaelic King of Dublin, is captured while trying to retake Dublin from the Cambro-Norman Richard de Clare, perhaps in company with Sweyn Asleifsson, and beheaded; before the end of the year, de Clare relinquishes possession of the city to his own liege lord, Henry.
- Pisa and Florence form an alliance against Lucca and Genoa.
- The successors of Robert Burdet leave Catalonia for Majorca, marking the end of the attempts to create a Norman principality in Iberia.
Births
- August 15 - King Alfonso IX of León
- Agnes of France, Empress consort of the Eastern Roman Empire, daughter of Louis VII of France
Deaths
- February 20 - Conan IV, Duke of Brittany
- April 3 - Philip of Milly, seventh Grand Master of the Knights Templar
- August 8 - Henry of Blois, bishop of Winchester
- November 8 - Baldwin IV, Count of Hainaut
- date unknown
- * Diarmait Mac Murchada, King of Leinster
- * Pulcelina of Blois, French Jew
- * Gleb of Kiev, Grand Prince of Kiev
- * Yesügei, father of Genghis Khan
