John of Gaunt's claims to the Castilian throne
Open-knowledge reference entry
John of Gaunt claimed the throne of Castile through his marriage to Constance of Castile in 1371. This proved to be an important component in the second phase of the Hundred Years War.
Aquitaine and Castile
English interference in the Kingdom of Castile started in early 1366 after Pedro the Cruel was expelled as part of an ongoing civil war after his illegitimate half-brother Henry of Trastamare invaded with a French army of 12,000 men led by the prominent commander Bertrand du Guesclin. Pedro was welcomed in English controlled Bordeaux by Edward III's oldest son, Edward the Black Prince who was also Prince of Aquitaine and Gascony, and John of Gaunt was sent with English troops to support Pedro in 1367 with Anglo-Gascon forces winning the Battle of Nájera in April and restoring Pedro to his throne.
Pedro refused to honour his agreement to fund the English and so with the Black Prince suffering from ill health the English returned to Aquitaine. The attempt to raise money to pay off the debt within Aquitaine started a rebellion which drew in the French King and restarted the Hundred Years War keeping the Black Prince away from Castile. Henry of Trastámara used this opportunity to lead a second more successful invasion that ended with Pedro's death at the Battle of Montiel in March 1369 with Henry becoming Henry II of Castile and providing naval support to French campaigns against Aquitaine and England. In 1372, the Castilian fleet defeated the English fleet in the Battle of La Rochelle.
Gaunt's marriage and claim
Pedro's elder daughter Constance now had a claim to the Castilan throne after her father's death. She took refuge in English controlled Bayonne.
The public source identifies “John of Gaunt's claims to the Castilian throne” as open-knowledge reference entry. This brief keeps that definition visible, then builds a research path around John, Gaunt's and claims.
Why this record matters
A short description can identify a subject without explaining its stakes. For “John of Gaunt's claims to the Castilian throne”, the useful work is to connect “open-knowledge reference entry” to the records capable of establishing context and consequence.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 17, 2026. The linked authority identifier is Q137168450. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1371, 1366, 1367 and 1369.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “John of Gaunt's claims to the Castilian throne”, its source revision and the description used here.
- Expand the search: follow John of Gaunt's claims to the Castilian throne primary sources, John of Gaunt's claims to the Castilian throne archive and John research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “John of Gaunt's claims to the Castilian throne”?
- Which institution is responsible for the underlying evidence?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “John of Gaunt's claims to the Castilian throne” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.