Alfonso the Magnanimous (also Alphonso; Catalan: Alfons) (1396 – 27 June 1458) was the King of Aragon (as Alfonso V), Valencia (as Alfonso III), Majorca, Sardinia and Corsica (as Alfonso II), and Sicily and Count of Barcelona (as Alfonso IV) from 1416 and King of Naples (as Alfonso I) from 1442 until his death. He was one of the most prominent figures of the early Renaissance and a knight of the Order of the Dragon.
In 1421 Queen Joan II of Naples, who had no children, adopted and named him as heir to the Kingdom of Naples, and Alfonso went to Naples. Here he hired the famous condottiero Braccio da Montone with the task of reducing the resistance of the other pretender, Louis III of Anjou, and his forces led by Muzio Attendolo Sforza. As Pope Martin V supported Sforza, Alfonso switched religious allegiance to the Aragonese antipope Benedict XIII. When Sforza also abandoned Louis, Alfonso seemed to have all his problems solved; however, his relationship with Joanna suddenly worsened, and in May 1423 he had her lover, and a powerful figure in the Neapolitan court, Gianni Caracciolo, arrested. After an attempt to arrest the queen herself failed, Joanna called Sforza who defeated the Aragonese milices near Castel Capuano in Naples. Alfonso fled to Castel Nuovo, but the help of a fleet of 22 galleys led by Giovanni da Cardona improved his situation. Sforza and Joanna ransomed Caracciolo and retreated to the fortress of Aversa. Here she repudiated her earlier adoption of Alfonso and, with support from Martin V, named Louis III as her heir instead. The Milanese Filippo Maria Visconti joined the anti-Aragonese coalition. Alfonso requested support from Braccio da Montone, who was besieging Joanna's troops in L'Aquila, but had to set sail for Spain, where a war had broken out between his brothers and the Kingdom of Castile. On his way towards Barcelona, he destroyed Marseille, a possession of Louis III.
In the late 1423 the Genoese fleet of Visconti moved in the southern Tyrrhenian Sea and easily conquered Gaeta, Procida, Castellammare and Sorrento. Naples, which was held by Alfonso's brother, Pedro, was besieged in 1424 by the Genoese ships and Joanna's troops, now led by Francesco Sforza, son of Muzio (who had died at L'Aquila). The city fell in the April of that year. Pedro, after a short resistance in Castel Nuovo, fled to Sicily in August. Joanna II and Louis III again took possession of the realm, although the true power was in the hands of Gianni Caracciolo.
An opportunity for Alfonso to reconquer Naples occurred in 1432, when Caracciolo was killed in a conjure. Alfonso tried to regain the favour of the queen, but failed, and had to wait for the death of both Louis (at Cosenza in 1434) and Joanna herself (February 1435). In her will, she bequeathed her realm to René of Anjou, Louis III's brother. This solution was opposed by the new pope, Eugene IV, who was nominal feudal lord of the King of Naples. As the Neapolitans had called for the French, Alfonso decided to intervene and, with the support of several barons of the kingdom, captured Capua and besieged the important sea fortress of Gaeta. His fleet of 25 galleys was met by the Genoese ships sent by Visconti, led by Biagio Assereto. In the battle that ensued, Alfonso was defeated and taken prisoner.
In Milan, however, he impressed his captor with his cultured demeanor and persuaded him to let him go by making it plain that it was not in Milan's interest to prevent the victory of the Aragonese party in Naples. Helped by a Sicilian fleet, Alfonso recaptured Capua and set his base in Gaeta in the February of 1436. Papal troops had invaded the Neapolitan kingdom, but Alfonso corrupted the cardinal Giovanni Vitelleschi, who commanded them, and his successes waned.
In the meantime, René had managed to reach Naples on may 19, 1438. Alfonso tried to besiege the city in the following September, but failed. His brother Pedro was killed during the battle. Castel Nuovo, where an Aragonese garrison resisted, fell to the Angevine mercenaries in the August of 1439. After the death of his condottiero Jacopo Caldora, however, René's fortune started to wane: Alfonso could easily capture Aversa, Salerno, Benevento, Manfredonia and Bitonto. René, whose possession included now only part of the Abruzzi and Naples, obtained 10,000 men from the pope, but the cardinal leading them signed a truce with Alfonso. Giovanni Sforza came with a reduced corps, as troops sent by Eugene IV had halted his father Francesco in the Marche.
Alfonso, who was provided with the most impressive artillery of the time, again besieged Naples. The siege began on November 10, 1441, and ended on June 2 of the following year. After the return of René to Provence, Alfonso easily reduced the remaining resistance and made his triumphal entrance in Naples on February 26, 1443, as the monarch of a pacified kingdom. In 1446 he conquered also Sardinia, becoming the head of the most important kingdom of western Europe.
Alfonso had been betrothed to María de Castilla (1401–1458; sister of Juan II of Castile) in Valladolid in 1408; the marriage was celebrated in Valencia during 1415. They failed to produce children. Alfonso had been in love with a woman of noble family named Lucrezia d'Alagno, who served as a de facto queen at the Neapolitan court as well as an inspiring muse.
His Spanish possessions were ruled for him by his brother John. Alfonso, by formally submitting his reign to the Papacy, obtained the consent of Pope Eugene IV that the Kingdom of Naples would go to his immature son Ferdinand. He died in Castel dell'Ovo in 1458, while he was planning the conquest of Genoa. At the time, Alfonso was at odds with Callixtus III, who died shortly thereafter.
Sicily and Sardinia were inherited by his brother John, who survived him.
He was also a powerful and consistent supporter of Scanderbeg, whom he decided to take under his protection as a vassal in 1451, shortly after the latter had scored his second victory against Murad II. In addition to financial assistance, he supplied the Albanian leader with troops, military equipment, and sanctuary for himself and his family if such a need should arise. This was because in 1448, while Scanderbeg was victoriously fighting off the Turkish invasions, three military columns, commanded by Demetrio Reres along with his sons Giorgio and Basilio, were dispatched to help Alfonso V defeat the barons of Naples who had rebelled against him.
Like a true prince of the Renaissance he favoured men of letters whom he trusted to preserve his reputation to posterity. He founded the Academy of Naples and, for his entrance in the city in 1443, had a magnificent triumphal arch added to the main gate of Castel Nuovo. This edifice, considered the most important civil piece of art of the time, was designed by Francesco Laurana. His devotion to the classics was exceptional even for the time. For example, Alfonso halted his army in pious respect before the birthplace of a Latin writer, carried Livy or Caesar on his campaigns with him, and his panegyrist Panormita even stated that the king was cured of an illness when a few pages of Quintus Curtius Rufus' history of Alexander the Great were read to him. However, the classics had not refined his taste, for he was amused by setting itinerant scholars, who swarmed to his court, to abuse one another in the indescribably filthy Latin scolding matches which were then the fashion.
After his conquest of Naples in 1442, Alfonso ruled by his mercenary soldiers and mercenary men of letters. In his Italian kingdom, he maintained the former political and administrative institutions; a unified General Chancellorship for the whole Aragonese reign was set in Naples, although the main functionaries were of Aragonese nationality. Apart from financial, administrative and artistical improvements, his other accomplishments in the Sicilian kingdom include the restoration of the aqueducts, the drainage of marshy areas, and the pavement of streets.