Alfoxso V., king of Portugal, surnamed the African, born in 1432, succeeded his father Duarte in 1438, died at Cintra, Aug. 28, 1481. During his minority the regency was held first by his mother and afterward by his uncle Dom Pedro, whose daughter the young king married on coming of age. A few years later Dom Pedro was declared a rebel and killed in battle, but Alfonso soon became convinced of his loyalty, paid great honors to his memory, and punished those who had traduced him. During his reign the Portuguese discovered and colonized Guinea. In answer to the call of Pope Calixtus III. for a general crusade against the Moslems, he equipped a fleet of 250 vessels for an expedition to Africa, and in 1458 landed near Tangier with 20,000 men. It was not until 13 years later that he found himself, after severe campaigns, master of Tangier and several other cities, his conquests surpassing in importance those of any other Portuguese monarch in Africa. Having been affianced to Joanna of Castile (his wife being dead), he proclaimed himself king of Castile and Leon, but was defeated at Toro in 1476 by Ferdinand the Catholic, and driven to seek assistance in France. There Louis XL treacherously held him prisoner till 1479, when he made peace with Ferdinand, and renounced his Spanish pretensions.

Joanna took the veil in 1480, and Alfonso was about to enter a monastery when he died of the plague. He founded at Coim-bra the first library in Portugal. For his zeal in ransoming Christian slaves he was called "the redeemer of captives.'"