Ferdinand and Isabella were cousins, whose 1469 marriage united the kingdoms of Castille and Aragon. The union created the nucleus of the nation of Spain and set the stage for the dramatic expansion of the Spanish Empire throughout the 16th century.
The long reign of Ferdinand and Isabella saw Spain united under a federal monarchy and the final success of the Reconquista, or reconquest, of Moorish territory in Granada. It was this united state that financed the voyage of Christopher Columbus and formalized the constitutional structure of Spain's government. Their reign was also marked by intolerance of minority religions, as both Muslims and Jews were subject to persecution under their rule.