Bishop Pelagius of Oviedo mentions Zaida as one of the king's two concubines and says that she was the daughter of Al-Mu'tamid ibn Abbad, ruler of the Taifa of Seville. In fact, she was his daughter-in-law, married to his son Abu Nasr Al-Fath al-Ma'mun, ruler of the Taifa of Córdoba. In March 1091, the Almoravid army besieged the city of Córdoba. Zaida's husband, who died during the siege on 26–27 March, sent his wife and children to Almodóvar del Río as a precautionary measure. After becoming a widow, Zaida sought protection at the court of the Leonese king and she and her children converted to Christianity; she was baptized with the name "Isabel" and became the king's concubine. She bore him one son: