Afonso III of Portugal (the Burgundian), fifth king of Portugal, was born in Coimbra in May 5, 1210 and died in February 16, 1279, in the same city. He was the son of Afonso II of Portugal by his wife, princess Urraca of Castile. Afonso succeeded his brother, king Sancho II of Portugal in 1247.

As the second son of Afonso III of Portugal, Afonso was not expected to inherit the throne, which was thought destined to his brother Sancho. He lived mostly in France, were he married the heiress Matilda in 1238, thus becoming count of Boulogne. In 1246, the conflicts between his brother the king and the church became unbearable. The pope Innocent IV then ordered Sancho II to be removed from the throne and be replaced by the count of Bolougne. Afonso II, of course, did not refuse the papal order and marched to Portugal. Since Sancho was not a popular king, the order was not hard to enforce. Sancho was exiled in Castile and Afonso III became king in 1247. To ascend the throne, he abdicated from the county of Boulogne and divorced Matilda. Determined not to commit the same mistakes as his brother, Afonso III paid special attention to what the middle class composed of merchants and small land owners had to say. In 1254, in the city of Leiria, Afonso III held the first session of the Cortes, the kingdom's general assembly, comprising the nobility, the middle class and representatives of all municipalities. He also made laws intended to restrain the upper classes from abusing the least favoured part of the population. Remembered as a notable administrator, Afonso III founded several towns, granted the title of city to many others and reorganized public administration.

Secured in the throne, Afonso III then proceeded to make war with the Muslim communities that still thrived in the south. In his reign Algarve became part of the kingdom following the capture of Faro - Portugal thus becoming the first Iberian Kingdom to complete his Reconquista. Following the successful war against the Moors, Afonso III had to deal with a political situation arising from the borders with Castile. The neighbouring kingdom considered that the newly acquired lands of Algarve should be Castilian, not Portuguese. This fact led to a series of wars between the countries. Finally, in 1267, a treaty was signed in Badajoz, determining that the southern border between Castile and Portugal should be the river Guadiana.

Afonso's marriages and descendants

• First wife: Matilda, countess of Boulogne
  • Roberto (1239)
• Second wife: princess Beatrix of Castile (1242-1303)
  • Branca, princess of Portugal (1259-1321), abbess of the Convent of Huelgas
  • Fernando (1260-1262)
  • Dinis, king of Portugal (1261-1325)
  • Afonso, prince of Portugal (1263-1312), married to princess Violante of Castile
  • Maria, princess of Portugal (1264-1284), religious in the Convent of Saint John in Coimbra
  • Sancha (1264-1279)
  • Constance (1266-1271)
  • Vicente (1268-1271)
• Natural children (among others)
  • Martim Chichorro (1250-1313)
  • Urraca Afonso, religious

See also: Kings of Portugal family tree

This article incorporates text from the public domain 1911 Encyclopædia Britannica.