In 1063, Fernando I of Leon sent his son, the infante Sancho to the aid of his vassal, Ahmad al-Muqtadir, king of the Taifa of Zaragoza when his city of Graus was being besieged by the forces of Ramiro I of Aragon. Consequently, Ramiro, who was Fernando's brother, would be defeated and killed. The expedition continued on towards Valencia, governed by Abd al-Malik ben Abd al-Aziz al-Mansur, with the intent on also turning that city into a vassal state.