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Duke of Medina Sidonia

peerage of Spain

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 19, 2026
Entity authorityQ112122143 ↗
Source-derived summary

Duke of Medina Sidonia (Spanish: Duque de Medina Sidonia) is a peerage grandee title of Spain in Medina-Sidonia, holding the oldest extant dukedom in the kingdom, first awarded by King John I of Castile in 1380. His father, Henry II of Castile (c.1334-1379), had an illegitimate son named Enrique de Castilla y de Sousa with Juana de Sousa, but after being made a Duke by his half-brother in 1380, he died in 1404, without a successor. The title then returned to the Crown.

The title of Duke of Medina Sidonia was awarded a second time on February 1445 by King John II of Castile to Juan Alonso de Guzmán, 3rd Count of Niebla (1410-1468).

They were once the most prominent magnate family of the Andalusian region, the best-known of whom, Don Alonso Pérez de Guzmán y Sotomayor, 7th Duke of Medina Sidonia, commanded the Spanish Armada at the end of the 16th century. The defeat at the hands of weather and the English in 1588 brought disgrace to this family. The House of Medina Sidonia traces its descent from Alonso Pérez de Guzmán (1265-1309).

Editorial summary

The public source identifies “Duke of Medina Sidonia” as peerage of Spain. This brief keeps that definition visible, then builds a research path around Duke, Medina and Sidonia.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1380, 1334, 1379, 1404—that can be checked directly. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with Duke, Medina and Sidonia providing the first useful test.
Editorial analysis

Why this record matters

A short description can identify a subject without explaining its stakes. For “Duke of Medina Sidonia”, the useful work is to connect “peerage of Spain” to the records capable of establishing context and consequence.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 19, 2026. The linked authority identifier is Q112122143. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1380, 1334, 1379 and 1404.

Critical limits

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.

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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.

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  2. Expand the search: follow Duke of Medina Sidonia primary sources, Duke of Medina Sidonia archive and Duke research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

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Source & attribution

This entry incorporates text from “Duke of Medina Sidonia” 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.