Alfonso V of Aragon (also Alfonso I of Naples) (1396 - June 27, 1458), surnamed the Magnanimous, was the King of Aragon and Naples and count of Barcelona from 1416 to 1458. He was a son of Ferdinand I of Aragon (a.k.a. Ferdinand of Antequera).
He represented the old line of the counts of Barcelona only through women, and was on his father's side descended from the House of Trastamara, a noble family of Castile, is one of the most conspicuous figures of the early Renaissance. No man of his time had a larger share of the quality called by the Italians of the day "virtue."
By hereditary right he was king of Sicily. He disputed the island of Sardinia with Genoa and conquered the kingdom of Naples. He fought and triumphed amid the exuberant development of individuality which accompanied the revival of learning and the birth of the modern world.
When he was a prisoner in the hands of Filipo Maria Visconti, Duke of Milan, in 1435, Alfonso persuaded his ferocious and crafty captor to let him go by making it plain that it was the interest of Milan not to prevent the victory of the Aragonese party in Naples.
Like a true prince of the Renaissance he favoured men of letters whom he trusted to preserve his reputation to posterity. His devotion to the classics was exceptional even in that 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 did not think it an incredible lie to say that the king was cured of an illness by having a few pages of Quintus Curtius read to him. The classics had not refined his taste, for he was amused by setting the wandering scholars, who swarmed to his court, to abuse one another in the indescribably filthy Latin scolding matches which were then the fashion.
Alfonso founded nothing, and after his conquest of Naples in 1442 ruled by his mercenary soldiers, and no less mercenary men of letters. His Spanish possessions were ruled for him by his brother John. He left his conquest of Naples to his bastard son Ferdinand; his inherited lands, Sicily and Sardinia, going to his brother John who survived him.