In the year 1452, during the Navarrese Civil War, Queen Juana Enríquez de Córdoba moved to the town, then called "Sos". There she gave birth to the infante Ferdinand on March 10, 1452, who later became Ferdinand II of Aragon, one of the Catholic Monarchs. His birth added "d'o Rei Catolico" to the name of the town, which translates as "of the Catholic Monarch".