Marriage of Isabella and Ferdinand

Timeline

1. 1468–1469Valladolid · ValladolidAfter the Treaty of Toros de Guisando recognized Isabella as heir, Henry IV still favored marrying her to Portugal. Isabella secretly corresponded with Aragon, and nobles such as Archbishop Carrillo of Toledo escorted Ferdinand covertly into Castile to evade court obstruction.
2. 1469Palace of Vivero · ValladolidOn October 19, 1469, Isabella and Ferdinand married at the Palace of Vivero in Valladolid. As they were close kin, papal dispensation documents were presented to prove the marriage valid; the ceremony was secret, intended to create a fait accompli.
3. 1471Rome · RomePope Sixtus IV ratified the consanguineous marriage by bull, removing canonical objections. The marriage formed the Catholic Monarchs' alliance between Castile and Aragon; after Isabella's accession in 1474 the two cooperated in the war of succession, becoming the political starting point of the Spanish composite monarchy.