So short was the pact concluded with Charles VIII, when the latter, about to attempt the Italian enterprise, wanted to secure his back from an attack by his dangerous neighbor: Ferdinando stipulated it to obtain the Rosellón and la Cerdaña for free (1492-1493 ); and after a while, with the league of 1495 and with the arms of the Great Captain, he managed to return to Fernando II of Naples the state taken from him by the French king. If then, after a few years, on 11 November 1500, with the secret treaty of Grenade the Aragonese agreed to agree with Louis XII to divide the South of Italy, this time too he did so in order to occupy without a shot being fired a part of the country, and prevent France, seizing the Neapolitan state, he would return to threaten the opposite Sicily and ensure effective dominance in the Mediterranean, where Catalonia and Valenza had a whole past, a present, and a hoped for future to defend: in reality, after a while they crossed arms again, and Fernando put them down only when the already allied French army was driven out of its last bastion, the fortress of Gaeta (January 1, 1504). Finally, if a brief period of friendship with the enemy followed, strengthened by the Treaty of Blois (12 October 1505) and by the marriage of the Aragonese sovereign widower with Germana di Foix, this was imposed on Fernando by his disagreements with his son-in-law Philip of Austria. ; and if the Spanish monarch agreed to participate in the League of Cambrai (December 1508), his adhesion was dictated by the desire to weaken the maritime power of Venice and to remove the Apulian cities that the Adriatic republic had occupied since the time of the expedition of Charles VIII: once the result was achieved he resumed his anti-French policy, joining the Holy League against Louis XII and persisting in his opposition even when the victory of Marignano strengthened the throne of Francis I, and Charles of Austria, son of Philip, began to follow a line of conduct independent from that chosen by his grandfather. However, even if dictated by Catalan-Aragonese interests, this policy was well in accord with Castilian interests. First of all, the alliance between Castile and France had been a consequence of the ever-renewing conflict between Castile and Aragon and the dynastic struggles that broke out in the bosom of that monarchy; and now the situation had completely changed. The conflict between the two already allied states had broken out even before Fernando’s accession to the throne of Aragon: that is, when, on the death of Henry IV, Louis XI had sided in favor of Alfonso V of Portugal to make him have the throne of deceased king; and until 1477 on the initiative of the Castilian monarch a European league had been formed against him, the first example of the future coalitions promoted by Spain against Charles VIII and Louis XII. Furthermore, Castile was directly interested in the success of the expansion policy in Navarre: and Fernando’s efforts yielded a result perhaps even greater than. hoped, because, after having subjected the country to a protectorate with the treaties of Tudela (1476), of Granata (1492), etc., the Aragonese king in 1512 took possession of the Spanish part of the monarchy. Also the conquest of Naples, which was followed by that of Oran (1509), of Bugia (1510), of Tripoli (1511) and the subjugation of Algiers and Tunis were such as to benefit Castile, which already from the time of Alfonso V of ‘Aragona had been called to take part in the events of southern Italy and with the victorious African exploits of Cisneros and Pedro Navarro saw the threat of an offensive return of the Muslims removed. And finally, due to the prevalence granted to it in the distribution of the fruits of the marvelous enterprises of Christopher Columbus, from which it had to derive, or rather should have obtained enormous advantages, Castile was called to imitate, in an immensely larger theater and with an Italian leader.

In domestic politics, the kingdom to which the greatest attention was turned was Castile, not only because it was the one that most needed it due to the still very backward conditions of its ethical-political life, but also because it, for its traditional peninsular politics, was the central nucleus of the new state organism, and because to consider it as such, in addition to Isabella for love of country, Ferdinand too had been drawn from his distrust of mischievous Catalonia and weak Aragon and from the affection that he, the son of a Castilian and descendant from the House of Castile, he had for his land of origin. But the same political systems also applied to the other monarchy. Which would have been immediately apparent from the deliberations that were taken in the Cortes of Toledo up to 1480: the centralization of powers in the hands of the monarch, the strengthening of his authority against all the disintegrating forces of the unity of government, the full autonomy of the sovereign in his work as administrator of the state. The prevalence of the high nobility ended not only because many of its fortresses were destroyed, it was forbidden to build new ones, the wealth of the lords reduced, forcing them to return courtiers to court or as quiet subjects in their lands; but also because the monarch had himself nominated grand master of the three orders of chivalry in Spain: of Calatrava (1487), of Alcantara (1494) of Spain Giacomo (1499); because the freedoms of the communes were protected and increased and the offices and jobs were entrusted to bourgeois, both faithful friends and intelligent collaborators of the sovereign;Santa Hermandad, ordered in the Cortes of Madrigal of 1476: terrible institution, with which banditry was repressed with frightening ferocity, ruin of the country and a means of domination for the great, and which was modified in 1498, when, for the goodness of the results obtained, it was no longer needed. Furthermore, the “Catholic king” always defended the ecclesiastical rights belonging to the crown against papal usurpations. Finally, reorganizing the monetary system, improving communications with the construction of roads and bridges, removing obstacles to free trade between Aragon and Castile, reorganizing the tax system, protecting industries as well as giving new possibilities for development to the activities of the Spaniards, enormously increased tax revenues and gave the state some financial autonomy, which increased the bankers’ confidence in the monarch and made possible strong credit openings with them, so that he always had at his disposal the means to carry out his expensive international politics. But, no doubt, in his absolutism he went too far, when he consented to the introduction into the state of the Inquisition to vigorously fight the heresies there. This permission was also granted because it was thought that by making Catholic the only religion allowed, through it a solid moral and political unity would be given to the country, and that court would become one of the most solid and powerful instruments of an absolute and centralizing government.

However, this only aggravated one of Spain’s fundamental evils, namely the inability to absorb and assimilate the hundreds of thousands of Jews and Muslims who inhabited it. And it was not long before we saw the sad effects of this policy, as well as of the expulsion of the Jews, a real economic speculation of the sovereign and of the bourgeoisie that had become politically powerful, to which it gave itself the character of a crusade: not the least of the intemperate Castile.