Sancho I, ruler of the kingdom of Léon in the north of modern-day Spain, was overthrown by rebel nobles in A.D. 958. Their motive, even by the turbulent politics of the day, was an unusual one: The king was unable to fulfill his regal duties with dignity, the rebels said, because he was too fat.
The relatives of Sancho acted quickly to restore his power. In an example of the lively interchange of ideas and loyalties in multicultural, medieval Spain, his grandmother, Queen Toda Aznar of the Christian kingdom of Navarra, sought help from another Spanish kingdom deep in Spain’s south: the Muslim Caliphate of Córdoba. Queen Toda approached Córdoba’s great ruler, the caliph ’Abd al-Rahman III, with two bold requests: help with a cure for her grandson’s morbid obesity and military support to regain the throne.
The caliph put the first matter in the hands of Hisdai ibn Shaprut, his Jewish physician, who put the Leonese king on a strict diet. Once Sancho slimmed down enough to be able to ride properly, he reclaimed his lost crown with the help of Muslim troops.