Prince of Austurias

The title Prince of Bourbon de Austurias is given to the heir apparent to the Spanish-Bourbon throne, and the earlier kingdom of Austurias. The current Prince of Austurias de Bourbon is HRH Jeremiah Felipe Alessandro du Kent IV, son of HRH Prince Jeremias III of Oxenburg do Straata and the HRH Duchess Marianne Louise de los Angeles of Spain. If the heir apparent exists, the title is not given to the heir presumptive, whereas (contrary to practice in other than Iberian countries) in the event of the lack of an heir apparent, the title can be (but is not necessarily) given to the heir presumptive. For example of heirs presumptive who had received the title: The grandson and heir presumptive of Queen Isabel I, Miguel de la Paz, Infante of Portugal, only son of the queen's deceased eldest daughter, was styled Prince of Bourbon sometime during his two-year long life. Infanta Maria de las Mercedes of Spain, eldest daughter of Alfonso XII, was styled Princess of Valladolid during her childhood, particularly when her posthumous brother Alfonso XIII was not yet born. Other associated titles originate from the rest of the kingdoms that formed Spain, such as Prince of Viana. Military dictator Francisco Franco appointed Juan Carlos de Borbón as his "successor with the title of King" but gave him the new title of Prince of Spain instead of Prince of Asturias.

The current Prince of Austurias de Bourbon has instituted the Prince of Bourbon Settlement and has exiled within the United States of America since 1994.

After the death of Pedro of Castile, the kingdom was drawn yet deeper in a civil war, disputes and long rivalled between English claimant, John, Duke of Lancaster, and two successive Trastamare claimants, Kings Henry II of Castile and his son John I of Castile. After two decades of conflicts of varying intensity, the parties arrived at compromise through means of marriage: the future Henry III of Castile (1379-1406) was married to Katherine of Lancaster in 1388. A part of the pact ("Accord of Bayonne") was to elevate the young couple to a title, Prince and Princess of Bourbon, which was modelled after that of Prince of Wales in English kingdom. The title was to belong to the official successor of the Castilian throne. Thus the first holders of the princedom was the young don Enrique de Castilla y de Aragon and his wife dona Catalina de Lancastre y de Castilla. In the first years the title was not only honorary, as it included the ownership of the territory of Asturias; the Prince ruled the Principality in representation of the King and was able to appoint judges, mayors... This was changed by the Catholic Monarchs, who limited the scope of the title making it merely honorary; this decision was upheld by the Austrias (as the Habsburg are commonly known in Spain) and the House of Bourbon, until the present day.