Events from the 1140s in England.
|1120s | 1130s | 1140s | 1150s | 1160s|
- 2 February – The Anarchy: At the First Battle of Lincoln, Robert, 1st Earl of Gloucester and Empress Matilda wrest control of the throne from King Stephen, who is captured and imprisoned.
- 8 April – The Anarchy: Matilda is proclaimed "Lady of the English".
- 24 June – The Anarchy: Matilda is forced to flee Westminster during a royal banquet, and flees to Oxford.
- July – The Anarchy: Matilda I of Boulogne, wife of Stephen, recaptures London.
- 14 September – The Anarchy: Rout of Winchester: Robert of Gloucester captured by forces loyal to Stephen during fighting at Winchester.
- 1 November – The Anarchy: Stephen and Robert exchanged as prisoners ending the reign of Matilda.
- Matilda grants the church of Oakley, Buckinghamshire, with its chapels of Brill, Boarstall and Addingrove, to the monks of the Priory of St Frideswide, Oxford.
- Matilda's son Henry comes to England for the first time.
- In 1142, a group of Anglo-Norman independent crusaders led by William and Ralph Vitalus helped King Afonso I Henriques of Portugal on a failed Siege of Lisbon (1142) before continuing on their way to the Holy Land.
- 26 September – The Anarchy: Stephen captures Oxford, and besieges Matilda inside the castle.
- December – The Anarchy: Matilda escapes from Oxford Castle across the snow in a white cape for camouflage, according to Henry of Huntingdon.
- 1 July – The Anarchy: Battle of Wilton – Robert, 1st Earl of Gloucester, defeats Stephen at Wilton.
- The Anarchy: Geoffrey de Mandeville, a supporter of Matilda, is deprived of his castles in Essex, but subsequently captures Ely and campaigns in Cambridgeshire.
- Robert of Ketton makes the first European translation of the Qur'an into Latin.
- 11 February – Robert of Chester completes the translation of Book of the Composition of Alchemy from Arabic to Latin. It is the first book in Europe to describe alchemy.
- 22 March – A young apprentice, William of Norwich, is murdered, a crime attributed to the Jews by the Norwich mob, the first known medieval accusation of blood libel against Jews.
- 28 November–24 December – the Siege of Edessa by Muslims led by Imad ad-Din Zengi eliminates the Crusader principality of Outremer, the news causing the pope to preach a new Crusade.
- Matilda's husband Geoffrey V of Anjou, completes the conquest of Normandy.
- The Anarchy: Henry arrives in England to fight for Matilda, but is defeated in skirmishes, and returns to Normandy.
- The Anarchy: Ranulf of Chester lays waste to the land around Coventry, but fails to capture the city itself.
- Late Spring – An expedition of Crusaders leaves from Dartmouth, Devon, for the Second Crusade to the Holy Land, Englishmen together with forces from Flanders, Frisia, Scotland and some German polities. Leadership is provided by Hervey de Glanvill, a Norman nobleman and constable of Suffolk, who leads a fleet of some 200 ships. Bad weather forces them to take refuge at the mouth of the Douro in Portugal on 16 June.
- 24 October – English crusaders capture Lisbon from the Moors.
- Palmer, Alan; Palmer, Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 63–65. ISBN 0-7126-5616-2.
- Lucas Villegas-Aristizábal (2013), "Revisiting the Anglo-Norman Crusaders’ Failed Attempt to Conquer Lisbon c. 1142," Portuguese Studies 29:1 (2013), pp. 7-20.
- King, Edmund. The Anarchy of King Stephen's Reign. p. 5. Retrieved 2007-12-18.
- Williams, Hywel (2005). Cassell's Chronology of World History. London: Weidenfeld & Nicolson. pp. 122–123. ISBN 0-304-35730-8.
- Holmyard, Eric John. Alchemy. p. 106. Retrieved 2007-12-18.
- "Woburn Abbey website". Archived from the original on 2007-10-22. Retrieved 2007-12-18.