Overview
King Lot , also spelled Loth or Lott (Lleu or Llew in Welsh), is a British monarch in Arthurian legend. He was introduced in Geoffrey of Monmouth's chronicle Historia Regum Britanniae as King Arthur's brother-in-law, who serves as regent of Britain between the reigns of Uther Pendragon and Arthur. He has appeared regularly in works of chivalric romance, alternating between the roles of Arthur's enemy and ally, and is often depicted as the ruler of Lothian and either Norway or Orkney. His literary character is likely derived from hagiographical material concerning Saint Kentigern, which features Leudonus as king of Leudonia (the Latin name for Lothian) and father of Saint Teneu.
Lot is generally portrayed as the husband of Arthur's sister or half-sister known by many names but most often as Anna, Gwyar, or variants of Morgause. The number and names of their children vary depending on the source, but usually they prominently include Gawain as well as other sons and sometimes daughters. Geoffrey suggests Lot as also the biological father of Mordred, and the much later prose romances identify him as the father of Gawain's younger brothers Agravain, Gaheris and Gareth while turning Mordred into an incestous son of Arthur.
Origins
A king of Lothian named Leudonus or Leudon of Leudonia can be found in both Latin and Welsh sources. A hagiography fragmentary, Vita Kentigerni, features Leudonus as the maternal grandfather of Saint Mungo. In this text, Leudonus has his daughter Teneu thrown from a cliff when he discovers that she had been raped and impregnated by Owain mab Urien. However, she survives the ordeal with divine protection and goes to Saint Serf's community, where she gives birth to Mungo. The story of Saint Mungo is placed around a century after the timeframe generally associated with Arthur. Welsh sources refer to Leudonus as Lewdwn or Llewdwn Lluydauc ("L[l]ewdwn of the Host") and make him king of the Gododdin people in the region of Hen Ogledd.
Geoffrey of Monmouth seems to refer to this earlier figure in the king whom he called Lot or Loth in his early 12th-century manuscript Historia Regum Britanniae. His sources are obscure, but the choice of name is likely based on its similarity to "Lodonesia", a Latinized name for Lothian.
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