|Covid-19|Norman conquest of England:
January 5 – Edward the Confessor of York dies. The Witenagemot proclaims Harold Godwinson King of England.
January 6 – Harold II is crowned King of England, probably in the new Westminster Abbey.
January (approx.) – Harold marries Ealdgyth, daughter of Earl Ælfgar, and widow of Welsh ruler Gruffydd ap Llywelyn.
March 20 – Halley's Comet reaches perihelion. Its appearance is subsequently recorded in the Bayeux Tapestry.
September 18 – Norwegian king Harald Hardrada lands on the beaches of Scarborough and begins his invasion of England.
September 20 – Battle of Fulford: Norwegian king Harald Hardrada defeats the northern English earls Edwin and Morcar.
September 25 – Battle of Stamford Bridge: Word of the Battle of Fulford reaches King Harold Godwinson, who decides to ride north to meet the invaders. Harold defeats Harald Hardrada and his brother Tostig Godwinson.
September 27 – William the Conqueror and his army set sail from the mouth of the River Somme, beginning the Norman conquest of England.
September 28 – Duke William of Normandy lands in England at Pevensey.
October 14 – Battle of Hastings, between King Harold II of England and Duke William of Normandy: Harold is killed by an arrow to the eye (some say he was killed by a band of Norman knights sent to assassinate him). William is victorious. This is considered the end of the Dark Ages or Early Middle Ages in England.
December 25 – Duke William of Normandy is crowned King William I of England in Westminster Abbey.
December 30 – Granada massacre: A Muslim mob storms the royal palace in Granada, crucifies Jewish vizier Joseph ibn Naghrela, and massacres most of the Jewish population of the city.
The Republic of Genoa, jealous of the recent successes of its former allies, launches a naval assault on the Republic of Pisa.
Magnus II Haraldsson is crowned King of Norway.
Upon the death of Stenkil, King of Sweden, two rivals named Eric battle for power in Sweden, both claiming the throne, until the next year.
Hedeby is destroyed by a Slavic, army and permanently abandoned.
Tain becomes the first town in Scotland to be chartered as a royal burgh.
Henry, Count of Portugal (d. 1112)
Irene Doukaina, Byzantine Empress (d. 1138)
January 5 – King Edward the Confessor
September 25 (killed at the Battle of Stamford Bridge):
King Harald III of Norway (Harald Hardråde) (b. 1015),
Tostig Godwinson, Earl of Northumbria, brother of King Harold II
October 14 (killed at the Battle of Hastings):
King Harold II of England
Leofwine Godwinson, brother of King Harold II
Gyrth Godwinson, brother of King Harold II
November 10 – John Scotus, bishop of Mecklenburg
Stenkil, king of Sweden since 1060
Ibn Butlan, Baghdad physician
Imam Bayhaqi, eminent Islamic scholar
Year 1066 (MLXVI) was a common year starting on Sunday of the Julian calendar. The year was a turning point in English history due to the Battle of Hastings and ensuing Norman conquest of England.