- April 18: Emperor Michael V of the Byzantine Empire attempts to remain sole Emperor by sending his adoptive mother and co-ruler Zoe of Byzantium to a monastery. This is not successful.
- April 19: Michael V of the Byzantine Empire is deposed by popular revolt. Zoe, Empress of the Byzantine Empire with co-rulers since 1028, becomes reigning Empress with her sister Theodora.
- June 8: Edward the Confessor becomes King of England.
- June 11: Empress Zoe marries for the third time and elevates her husband to the throne as Constantine IX.
- George Maniaces, Byzantine general in Sicily, revolts against Constantine IX.
- Harald III of Norway, at this time leader of the Varangian Guard in the Byzantine Empire, returns to Norway, possibly because of his involvement in Maniaces' revolt.
- Magnus I of Norway becomes King of Denmark.
- The Normans in Italy move their capital to Melfi.
- Abad II succeeds his father to the throne of Sevilla.
- The Almoravids, led by Abdullah Ibn Yasin, invade Morocco.
- Byzantine-Arab Wars: The Byzantines conquer Edessa, returning to Christian hands after 400 years of Islamic rule.