The victor of Caspe, Fernando de Antequera, soon made clear his intention of continuing the Mediterranean policy of his Catalan predecessors. He immediately secured investiture of the kingdoms of Sicily and Sardinia from the antipope, Benedict XIII, since, during the interregnum, there had been a real risk that they might be lost to the crown. Similarly, he made sure of his title to the kingdom of Corsica, which had never been totally subdued. He then began to settle the problems of those regions with determination. He pacified Sicily and modernised its administration, side-stepping the island’s persistent requests for a king of its own by sending his son, Juan of Penafiel, as viceroy. In Sardinia he stopped the viscount of Narbonne in his attempt to take over Alghero, and prevented a general insurrection by reaching agreement with the marquis of Oristano, thus not only keeping the island under Aragonese control but boosting its depleted population with a new wave of Catalonian and Aragonese immigrants. Fernando’s ambitions, however, extended further to the newly acquired Naples, his diplomatic efforts being aimed at creating a climate favourable to an enlargement of Aragonese dominion in the Mediterranean. He thus toyed with the idea of a marriage between his son, Joan, and Giovanna II of Anjou-Durazzo, queen of Naples. These projects, along with his defence of Catalonian trading interests in Egypt and on the Barbary Coast, were the most valuable part of the inheritance which he bequeathed to his son, Alfonso V ‘the Magnanimous’. Even under Alfonso, this policy, termed ‘road of the islands’ (ruta de las islas) by modern Spanish historians, in conjunction with Catalan commercial expansion in the direction of the great spice emporia (ruta de las especias), was no crude alternative to those traditional Trastamaran interests in Castile which sought to establish their dominion throughout the entire Iberian peninsula. Within Iberia itself, even after his election to the throne of Aragon, Fernando I did not step down as regent of Castile, ruling in the name of his brother, Enrique III. Fernando’s second son, Juan, was created duke of Penafiel in Castile, and his other sons, Enrique, Sancho and Pedro, were placed at the head of the powerful military orders of Santiago, Calatrava and Alcantara respectively. The marriages of his children, too, were arranged to consolidate Aragonese power. In what has been termed the marriage policy of the infantes of Aragon, Alfonso, his first son, married Marla, infanta of Castile, in 1415, while his daughter, Marla, became the wife of the future Juan II of Castile three years later.
After 1442, following the conquest of Naples by Alfonso V, who had succeeded his father in 1416, the policy of Mediterranean expansion so dear to Catalan hearts finally became more important than expansion in the Iberian peninsula. Alfonso’s extremely personal view of Mediterranean and Italian policy was inspired by the myth of humanistic glory, which caused him to act more and more as a rex Italicus. This, however, did not prevent his policies from offering significant benefits to Catalans who, within the ‘realm’, acquired financial positions previously reserved for Florentine merchants and bankers. Although, even at the beginning of his reign, Alfonso had established that, on his death, the kingdom of Naples would be separated from his other possessions and given to his illegitimate son, Ferrante (Ferdinando), while the rest of his inheritance would pass to his brother, Joan (II), this should not be taken as an admission on his part that, without constant and expensive controls, the new conquests could not be maintained.
Alfonso’s sweeping vision of the Mediterranean situation led to a plan for the economic integration of all territories of the crown of Aragon: those close to home were to undergo industrial development, while those further away (Sicily, Sardinia and Naples) were to have their agricultural potential developed. An enlarged national (Catalan) fleet would encourage trade between all the regions (mutua e reciproca contractacio e comerci), while protectionist laws would help keep Florentine merchants and Italian vessels out of this huge market. With the Peace of Lodi and membership of the Italian League in 1455, Alfonso was obliged to suspend his policy against the Florentines, who had already been expelled from his kingdoms. Their return to Naples, however, in no way affected the position of Catalans in the commercial and banking fields as, even under Ferrante, they retained direct control of the ‘realm’s’ financial institutions.