Afonso V of Portugal Afonso V ( , originally " Affonso " ) KG ( 15 January 1432 – 28 August 1481 ) , called the African ( ) , was King of Portugal and the Algarves . His sobriquet refers to his conquests in Northern Africa . Early life . Afonso was born in Sintra , the eldest son of King Edward of Portugal by his wife , Eleanor of Aragon . Afonso V was only six years old when he succeeded his father in 1438 . During his minority , Afonso V was placed under the regency of his mother in accordance with a will of his late father . As both a foreigner and a woman , the queen was not a popular choice for regent . Opposition rose and without any important ally among the Portuguese aristocracy other than Afonso , Count of Barcelos , the illegitimate half brother of King Edward and count of Barcelos , the queen ' s position was untenable . In 1439 , the Portuguese Cortes ( assembly of the kingdom ) decided to replace the queen with Infante Peter , Duke of Coimbra , the young king ' s oldest uncle . His main policies were concerned with avoiding the development of great noble houses , kingdoms inside the kingdom , and concentrating power in the person of the king . The country prospered under his rule , but not peacefully , as his laws interfered with the ambition of powerful nobles . The count of Barcelos , a personal enemy of the Duke of Coimbra ( despite being half - brothers ) eventually became the king ' s favourite uncle and began a constant struggle for power . In 1442 , the king made Afonso the first Duke of Braganza . With this title and its lands , he became the most powerful man in Portugal and one of the richest men in Europe . To secure his position as regent , Peter had Afonso marry his daughter , Isabella of Coimbra , in 1445 . But on 9 June 1448 , when the king came of age , Peter had to surrender his power to Afonso V . The years of conspiracy by the Duke of Braganza finally came to a head . On 15 September of the same year , Afonso V nullified all the laws and edicts approved under the regency . The situation became unstable and , in the following year , being led by what he afterwards discovered to be false representations , Afonso declared Peter a rebel and defeated his army in the Battle of Alfarrobeira , in which his uncle ( and father - in - law ) was killed . After this battle and the loss of one of Portugal ' s most remarkable infantes , the Duke of Braganza became the " de facto " ruler of the country . Invasion of Morocco . Afonso V then turned his attentions to North Africa . In the reign of his grandfather , John I , Ceuta had been conquered from the king of Morocco , and now the new king wanted to expand the conquests . The king ' s army conquered Alcácer Ceguer ( 1458 ) , Tangiers ( won and lost several times between 1460 and 1464 ) and Arzila ( 1471 ) . These achievements granted the king the nickname of " the African " . The king also supported the exploration of the Atlantic Ocean led by prince Henry the Navigator but , after Henry ' s death in 1460 , he did nothing to continue this course of action . Administratively , Afonso V was a passive king . He chose not to pursue the revision of laws or development of commerce , preferring instead to preserve the legacy of his father Edward and grandfather John I . In 1452 , Pope Nicholas V issued the papal bull Dum Diversas , granting Afonso V the right to reduce " Saracens , pagans and any other unbelievers " to hereditary slavery . This approval of slavery was reaffirmed and extended in the Romanus Pontifex bull of 1455 ( also by Nicholas V ) . These papal bulls came to serve as a justification for the subsequent era of slave trade and European colonialism . When the campaigns in Africa were over , Afonso V found new grounds for battle in the Iberian Peninsula . In neighbouring Castile , a huge scandal with political and dynastic implications had arisen . In 1474 , King Henry IV of Castile died without a male heir . From his two marriages , only a daughter , Joanna of Castile , had been born . But her paternity was questioned , as rumour said the king was impotent and the queen , Joan of Portugal , had an amorous affair with a nobleman named Beltrán de La Cueva . The birth of princess Joanna in 1462 , openly called " La Beltraneja " , caused the separation of her parents . She was never considered legitimate and , when the king was dying , no one took her as a serious contender for the crown . Her half - aunt , the future Queen Isabella I of Castile , was due to inherit the crown , but Afonso V was keen to interfere with the succession in Castile . In 1475 he married his niece Joanna , La Beltraneja , whom he considered the legitimate heir to the crown . Since her adulteress mother was his own sister , Afonso V had not only ambition , but the family honour to protect . He proclaimed himself King of Castile and León and prepared to defend his wife ' s rights . After the indecisive Battle of Toro in 1476 against King Ferdinand II of Aragon , the husband of Isabella I of Castile , he went to France to obtain the assistance of Louis XI , but finding himself deceived by the French monarch , he returned to Portugal in 1477 in very low spirits . Disillusioned and depressed , he fell into a deep melancholy and abdicated in favour of his son , John II . After this , he retired to a monastery in Sintra where he died in 1481 . His death was mourned in the country , by the people who loved the king , and by the nobles who were starting to fear his successor . Marriages and descendants . Afonso was first married to his cousin Isabella of Coimbra in 1447 . Isabella died in 1455 and Afonso married again ( although not recognized by the Papacy ) in 1475 , this time to Joanna of Castile ( known as " La Beltraneja " ) , daughter of Henry IV of Castile and Joan of Portugal . This marriage was an attempt to inherit the throne of Castile as Joan was the sole daughter of Henry IV . Afonso ' s attempts to take over the throne of Castile were not successful after he lost a short war with Isabella of Castile and Ferdinand of Aragon . References . Articles