Alfonso V of Aragon, who won from his contemporaries the title `the Magnanimous', was one of the most brilliant of the fifteenth-century monarchs. Professor Ryder follows him from childhood in the chivalric world of Castile, to the newly-acquired states of Aragon, and his subsequent accession to the Aragonese throne. Pulled by powerful dynastic interests towards intervention in the turbulent world of Castilian politics, Alfonso eventually broke free to pursue his own ambitions in the central Mediterranean. Here he conquered Naples, bent the papacy to his will, broke the power of Genoa, and strove against Turkish advances in the Balkans.Based on extensive archival research, this is the first complete biography of Alfonso. It paints a vivid picture of political and cultural developments during his reign.