João I of Portugal (1357–1433)

João I of Portugal, born on April 11, 1357, was king of Portugal (1385–1433) and founder of the house of Aviz (Avis). The illegitimate son of Pedro I, he ascended to power first as regent in 1383 and then as king despite opposition from the aristocracy and upper clergy. Through the Portuguese defeat of Castilian forces in the Battle of Aljubarrota (1385), the establishment of close alliances with England and Burgundy, and the creation of a new aristocracy with middle-class roots, João centralized power in the hands of the monarchy.

The marriage of João to Philippa of Lancaster, daughter of John of Gaunt, reinforced Portuguese-English relations and produced several children who contributed to the future of independent Portugal. Isabel was wed to Philip the Good, duke of Burgundy, thereby solidifying relations with Flanders. Henrique, or Henry the Navigator, devoted his energies to increasing the economic power of Portugal by attempting to establish a direct trade route to the Far East. Duarte (b. 1391) succeeded his father but died in 1438, leaving his brother Pedro as regent. Pedro's regency assured the house of Aviz's position as the ruling dynasty of Portugal until 1580, when Castilian forces seized the throne for Philip II of Spain. The house of Aviz promoted intensive overseas exploration and expansion not only to perpetuate the Aviz name but also to placate their initial supporters, the Portuguese mercantile community. João died on August 4, 1433.

See alsoPhilip II of Spainxml .

BIBLIOGRAPHY

"The Conquest of Ceuta: Being the Chronicle of the King Dom João I." In Conquests & Discoveries of Henry the Navigator, Being the Chronicles of Azurara, edited by Virginia de Castro e Almeida, translated by Bernard Miall. London: George Allen & Unwin, 1936.

Livermore, H. V., ed., Portugal and Brazil. Oxford, Clarendon Press, 1953.

                                   Lesley R. Luster