John, Constable of Portugal

Infante John, Constable of Portugal (Portuguese: João, Portuguese pronunciation: [ʒuˈɐ̃w̃]; 13 January 1400 – 18 October 1442) was a Portuguese infante (prince) of the House of Aviz, Constable of Portugal and master of the Portuguese Order of St. James (Santiago). In Portugal, he is commonly referred to as the O Infante Condestável ("the Constable Prince").

Infante John
Constable of Portugal
Lord of Reguengos de Monsaraz, Colares and Belas
John of Reguengos (St. Vincent Panels).jpg
Detail from the St. Vincent Panels by Nuno Gonçalves, often believed to be a portrait of John of Reguengos, the Constable Prince.
Born13 January 1400
Santarém, Kingdom of Portugal
Died18 October 1442(1442-10-18) (aged 42)
Alcácer do Sal, Kingdom of Portugal
SpouseIsabella of Barcelos
Diogo, Constable of Portugal
Isabella of Portugal, Queen of Castile
Infanta Beatrice, Duchess of Viseu
FatherJohn I of Portugal
MotherPhilippa of Lancaster
ReligionRoman Catholicism

Early lifeEdit

Infante John was the son of King John I of Portugal and his wife Philippa of Lancaster. John and his brothers Edward, Peter, Henry and Ferdinand, sister Isabella and half-brother Afonso, constitute what Portuguese historians have traditionally labelled the 'illustrious generation' (Ínclita Geração)

Royal careerEdit

He was invested as the 1st Lord of Reguengos de Monsaraz, Colares and Belas shortly after. In October 1418, at the king's request, Pope Martin V approved the appointment of Infante John as the 10th Master of the Order of St. James of the Sword, bringing the old military order into the hands of the royal family.[1] That same year (1418), John and his brother Henry the Navigator led a relief fleet to Ceuta and helped lift the Siege of Ceuta.

After the death of Nuno Álvares Pereira in 1431, Infante John was appointed the 3rd Constable of Portugal. As a result, John is frequently characterised by the appellation O Infante Condestável ("The Constable Prince").

Infante João was Lord of Reguengos
de Monsaraz, Belas and Colares.

After King John I's death in 1433, John's eldest brother ascended the throne as king Edward of Portugal. In 1437, Infante John joined another brother Peter, Duke of Coimbra, in arguing against a projected Portuguese expedition to seize Tangier that led to the Battle of Tangier. The campaign ended in disaster. After the Tangier fiasco, John urged the ratification of a treaty with Marinid Morocco that called for the relinquishment of Ceuta in exchange for his captive brother Ferdinand the Holy Prince. The Cortes refused, and Ferdinand was left to die in captivity.

Duke of Coimbra RebellionEdit

King Edward died in September 1438, leaving a young son to ascend the throne as king Afonso V of Portugal under the regency of his widow Eleanor of Aragon. This was an unpopular arrangement among the common people of the country, who feared Eleanor would be a puppet of the high nobility who sought to recover the political privileges they lost during the revolution of the 1380s. The prospect of civil war raised its head. To forestall a rebellion, Infante John quickly seized control of Lisbon and oversaw the assembly of a burgher-packed Cortes to elect his brother Peter of Coimbra as regent for his nephew Afonso V. The high nobility, led by his half-brother Afonso of Barcelos, urged Eleanor to hold fast, and a tense power-sharing regency arrangement was agreed upon between Peter and Eleanor.

Peter of Coimbra relied on his close alliance with Infante John to secure the lion's share of power during the first few years of the regency. Infante John's sudden death in October 1442 was a terrible blow to Peter, who thereafter found it increasingly difficult to fend off the aspirations of his half-brother Afonso of Barcelos.

Sepulcher of Infante John and Isabella of Barcelos in Batalha Monastery

Regent Peter appointed John's son Diogo of Portugal to succeed his father as Master of the Order of Santiago and Constable of Portugal.

Marriage and IssueEdit

In 1424, John married his half-niece Isabella of Barcelos, daughter of his half-brother Afonso of Barcelos. The couple had four children:



  1. ^ Bull of Pope Martin V appointing John master of Santiago can be found in Monumenta Henricina, vol. 2, p.301
  2. ^ a b John I, King of Portugal at the Encyclopædia Britannica
  3. ^ a b c d e f g h i j k Armitage-Smith, Sydney (1905). John of Gaunt: King of Castile and Leon, Duke of Aquitaine and Lancaster, Earl of Derby, Lincoln, and Leicester, Seneschal of England. Charles Scribner's Sons. p. 21. Retrieved 17 July 2018.
  4. ^ a b Peter I, King of Portugal at the Encyclopædia Britannica
  5. ^ a b c de Sousa, Antonio Caetano (1735). Historia genealogica da casa real portugueza [Genealogical History of the Royal House of Portugal] (in Portuguese). Vol. 2. Lisboa Occidental. p. 4.
  6. ^ a b Afonso IV, King of Portugal at the Encyclopædia Britannica
  7. ^ a b de Sousa, Antonio Caetano (1735). Historia genealogica da casa real portugueza [Genealogical History of the Royal House of Portugal] (in Portuguese). Vol. 1. Lisboa Occidental. p. 316.
  8. ^ a b von Redlich, Marcellus Donald R. Pedigrees of Some of the Emperor Charlemagne's Descendants. Vol. I. p. 64.
  9. ^ Mosley, Charles, ed. (1999). Burke's Peerage and Baronetage. Vol. 1 (106th ed.). Crans, Switzerland: Burke's Peerage (Genealogical Books) Ltd. pp. 227–228.

"Nobreza de Portugal e do Brasil" – Vol. I, pages 296–297. Published by Zairol Lda., Lisbon 1989.