The unification of the crowns of Aragon and Castile laid the basis of which modern-day European country?
Joanna of Castile Joanna of Castile Joanna (6 November 1479 – 12 April 1555), known historically as Joanna the Mad (), was Queen of Castile from 1504, and of Aragon from 1516. Modern Spain evolved from the union of these two crowns. Joanna was married by arrangement to Philip the Handsome, Archduke of the House of Habsburg, on 20 October 1496. Following the deaths of her brother, John, Prince of Asturias, in 1497, her elder sister Isabella in 1498, and her nephew Miguel in 1500, Joanna became the heir presumptive to the crowns of Castile and Aragon. When her mother Queen Isabella I
Philip I of Castile giving birth to a son named Miguel da Paz, to whom succession to the united crowns of Castile, Aragon and Portugal now fell; however, the infant was sickly and died during the summer of 1500. The succession to the Castilian and Aragonese crowns now fell to Joanna. Because Ferdinand could produce another heir, the Cortes of Aragon refused to recognize Joanna as heir presumptive to the Kingdom of Aragon. In the Kingdom of Castile, however, the succession was clear. Moreover, there was no Salic tradition which the Castilian Cortes could use to thwart the succession passing to Joanna. At this