Eleanor of Guzman or Leonor Núñez de Guzmán (1310 in Sevilla-1351 in Talavera de la Reina) was a Castilian noblewoman and long-term mistress to Alfonso XI of Castile. She was the mother of King Henry II of Castile.
Eleonor was the daughter of a Jewish merchant and nobleman Pedro Núñez de Guzmán and his wife, Beatriz Ponce de León, a great-granddaughter of King Alfonso IX of León. Her parents married Eleonor off as a young girl to Juan de Velasco.
Eleanor's husband died in 1328, he was twenty years old. Soon later, in Seville she met King Alfonso XI. He was so impressed by her beauty that he made her his mistress. He preferred Eleanor to his wife Maria of Portugal, daughter of Alfonso IV of Portugal, who he had married in 1328 for political reasons. After Maria's son and heir, the future Peter of Castile, was born 1334, Alfonso left Maria and lived with Eleanor instead. The humiliated rightful queen resented her unfaithful husband publicly and asked him to show preference for his mistress. The king gave Eleonor: Huelva, Tordesillas, Medina-Sidonia and others, he also set up her household in Seville and was aloud to hear political matters. Many became annoyed by Alfonso's behaviour and as a result, the Pope intervened by making Portugal invade Castile.
The King died on the 27 March 1350 and was succeeded by his legitimate son Peter and his wife Maria served as regent. Maria was thirsting for revenge and she got what she wanted. She had Eleanor imprisoned and later executed in 1351[1]. Eleanor's death did not end the fighting though, her son Henry and Maria's son Peter fought eachother for Castile, Henry later won and became King of Castile.