1086
Year 1086 was a common year starting on Thursday of the Julian calendar.
Events
By place
Europe
- October 23 - Battle of Sagrajas: Spanish forces under King Alfonso VI of Castile are defeated by the Moors and their allies, the Almoravids, who have been invited to help on orders by Emir Al-Mu'tamid ibn Abbad.
- Siege of Syracuse - Norman forces under Count Roger I conquer Syracuse, the last Muslim stronghold in Sicily.
England
- August 1 - King William the Conqueror calls for a meeting at Old Sarum, where he invites his major vassals and tenants-in-chief to swear allegiance to him. This is known as the Oath of Salisbury.
- The Domesday Book is completed. Drawn up on the orders of William I; it describes in detail the landholdings and resources in England.
- The population in England is estimated to be 1.25 million citizens with 10% living in boroughs.
Seljuk Empire
- Summer - Suleiman ibn Qutulmish, ruler of the Turks in Rum, is killed by Emir Tutush I in the battle of Ain Salm near Antioch. Suleiman's 7-year-old son Kilij Arslan I is captured and transferred as hostage to Isfahan.
- Sultan Malik-Shah I rebuilds the Imam Ali Mosque in Najaf, after it was destroyed by fire.
By topic
Religion
- May 24 - Pope Victor III succeeds Gregory VII as the 158th pope of the Catholic Church, though he does not accept election until 1087.