Diogo of Portugal (1425–1443) was a

Portuguese Portuguese may refer to: * anything of, from, or related to the country and nation of Portugal ** Portuguese cuisine, traditional foods ** Portuguese language, a Romance language *** Portuguese dialects, variants of the Portuguese language ** Portu ...

royal prince, who briefly served as

Constable of Portugal {{Short description, Defunct office created by King Ferdinand I of Portugal Constable of Portugal ( pt, Condestável de Portugal) was an office created by King Ferdinand I of Portugal in 1382, to substitute the High Standard-bearer ('' Alferes-Mor'' ...

and Master of the

Order of Santiago The Order of Santiago (; es, Orden de Santiago ), is a religious and military order founded in the 12th century. It owes its name to the Patron Saint of Spain, "Santiago" (St. James the Greater). Its initial objective was to protect the pilgri ...

. Diogo was the eldest son of

John, Lord of Reguengos de Monsaraz Infante John, Constable of Portugal ( pt, João, ; 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, ...

Infante ''Infante'' (, ; f. ''infanta''), also anglicised as Infant or translated as Prince, is the title and rank given in the Iberian kingdoms of Spain (including the predecessor kingdoms of Aragon, Castile, Navarre, and León) and Portugal to th ...

of Portugal, and of his wife (and niece)

Isabella of Barcelos Isabel of Barcelos (October 1402 – 26 October 1466), also known as Isabel of Braganza, was a lady of the Portuguese nobility during the Late Middle Ages. She was the daughter of Afonso I, Duke of Braganza and Beatriz Pereira de Alvim, and she ...

. Through his father, Diogo was the grandson of King John I of Portugal and through his mother, the grandson of

Afonso of Barcelos Dom Afonso I of Braganza (; 10 August 1377 – 15 December 1461) was the first duke of Braganza and the eighth count of Barcelos. He founded the House of Braganza, the most powerful and wealthy dynasty in Portugal. His descendants became high-ra ...

(future first

duke of Braganza The title Duke of Braganza ( pt, Duque de Bragança) in the House of Braganza is one of the most important titles in the peerage of Portugal. Starting in 1640, when the House of Braganza acceded to the throne of Portugal, the male heir of the P ...

). John of Reguengos had been the master of the

since 1418 and

since 1431. Upon John's premature death in October 1442, the Portuguese

regent A regent (from Latin : ruling, governing) is a person appointed to govern a state '' pro tempore'' (Latin: 'for the time being') because the monarch is a minor, absent, incapacitated or unable to discharge the powers and duties of the monarchy ...

, Peter of Coimbra decided to appoint John's son Diogo as the new Constable of Portugal. Diogo was elected on 24 January 1443, as 11th Master of the Order of Santiago. Diogo died a few days later, without issue. Peter appointed his own son, also named

Peter Peter may refer to: People * List of people named Peter, a list of people and fictional characters with the given name * Peter (given name) ** Saint Peter (died 60s), apostle of Jesus, leader of the early Christian Church * Peter (surname), a sur ...

, to succeed him as constable. These appointments were contested by Diogo's half-uncle (and grandfather), Afonso, Count of Barcelos. Afonso had married the daughter of the late beatified constable

Nuno Álvares Pereira D. Nuno Álvares Pereira, O. Carm. (; 24 June 1360 – 1 November 1431) was a Portuguese general of great success who had a decisive role in the 1383-1385 Crisis that assured Portugal's independence from Castile. He later became a mystic ...

, and believed their son, Afonso of Ourem, had superior rights to succeed as Constable of Portugal. Peter of Coimbra challenged Barcelos and Ourem to provide documentary proof of the legitimacy of this lineage (which they were unable to produce). Peter of Coimbra attempted to mollify them by creating the title of

Duke of Braganza The title Duke of Braganza ( pt, Duque de Bragança) in the House of Braganza is one of the most important titles in the peerage of Portugal. Starting in 1640, when the House of Braganza acceded to the throne of Portugal, the male heir of the P ...

, and investing it in Afonso of Barcelos. However, this failed to heal the breach between Peter and Afonso, which would only grow with time.

Ancestry

References

External links

Genealogical information on Diogo, Constable of Portugal (in Portuguese)

Bibliography

"Nobreza de Portugal e do Brasil" – Vol. I, page 297. Published by Zairol Lda., Lisbon 1989. Portuguese infantes House of Aviz 1425 births 1443 deaths 15th-century Portuguese people Constables of Portugal {{Portugal-royal-stub