Earl of York
In Anglo-Saxon England, the Earl of York or Ealdorman of York was the ruler of the southern half of Northumbria. The title ealdorman is Anglo-Saxon, while earl comes from Old Norse eorl. The ealdormanry (earldom) seems to have been created in 966 following a period when the region was under the control of Oswulf, already high-reeve of Bamburgh in northern Northumbria, from about 954, when Norse rule at York came to an end.
- William le Gros, having already been charged with the defence of the city of York, was created earl by King Stephen in 1138. He was the king's administrator of all Yorkshire. In 1155 he was forced to relinquish the earldom to King Henry II.
- Otto of Brunswick was created earl of York by King Richard I in 1190. Otto had difficulty in proving the authenticity of this grant to his vassals in Yorkshire. He probably visited Yorkshire only once in 1191, although he continued to claim the revenues of the earldom after being elected King of Germany in 1198.
- George Molyneaux (2017). The Formation of the English Kingdom in the Tenth Century. Oxford University Press. pp. 177–179. In footnote 289, he provides the following list with dates based on charter witnesses: "Thored (witnesses 979–c.989), Ælfhelm (993–1005), Uhtred (1009–1015), Erik (1018–1023), Siward (1033–1053×1055), Tostig (1059–1065), and Morcar (1065)."
- Paul Dalton (2004), "William le Gros, count of Aumale and earl of York (c. 1110–1179), magnate". Oxford Dictionary of National Biography. Retrieved 28 June 2019.
- Kate Norgate (1887). England Under the Angevin Kings. Macmillan. p. 373 n. 1.
- Joseph Patrick Huffman (2000). "Richard the Lionheart and Otto IV: Itinerant Kingship and the City of Cologne". The Social Politics of Medieval Diplomacy: Anglo-German Relations (1066–1307). University of Michigan Press. pp. 157–58.
- Frank McLynn (2007). Lionheart and Lackland: King Richard, King John and the Wars of Conquest. Vintage. p. 390.