The Breton project Linked Brittany continues its research in European archives. Bretaigne DAO has just submitted a scientific contribution to EuroMed2026 dedicated to the comparison of historical documents and their digital interconnection. The application has been registered and is awaiting evaluation by the scientific committee.
A scientific application to enhance Breton archives
On October 12, 2026, Bretaigne DAO submitted a scientific contribution to the international conference EuroMed2026, dedicated to digital cultural heritage. This proposal, registered under number 78, presents the initial methodological orientations of the Linked Brittany project. Its goal is to better identify and connect the historical sources of the Duchy of Brittany preserved in European archives. The conference will take place online from November 2 to 5, 2026. The contribution is currently under review by the scientific committee. A response to the authors is expected by October 27. This process does not yet constitute an acceptance of our communication.
Documents scattered across several countries
The history of the Duchy of Brittany extends far beyond the borders of its former territories. Diplomatic acts, correspondence, and administrative records are now preserved in several European countries. To study them, researchers sometimes have to confront documents written in different languages, at different dates, and bearing archival references that have changed over the centuries. Bretaigne DAO has been conducting research in these collections for several months. This analysis gradually allows for the identification of originals, old copies, and documentary editions. It also reveals the difficulties encountered when the archives of the same historical episode are scattered among several institutions.
In 1372, a power of attorney between Biscay and Brittany
One example concerns the relations between the communities of Biscay and the Duchy of Brittany. A document preserved in the Archives départementales de Loire-Atlantique, under reference E 201/7, dates back to 1372. It corresponds to a power of attorney given by the inhabitants of several Biscayan towns to Jean de Saillo to negotiate an alliance with the Duke of Brittany. The scientific database SIGILLA describes this act and its seal. This source is particularly interesting because it shows the difference between an authorization to negotiate and the agreement that this negotiation could produce. It would be historically incorrect to directly present the power of attorney as the text of the sought treaty.
New diplomatic leads in Simancas
In Spain, the Archivo General de Simancas preserves several documents related to the diplomatic relations between François II, Duke of Brittany, and the crowns of Castile and Aragon. An initial article published by Bretaigne DAO on the Agence Bretagne Presse presented the acts from November and December 1483. These documents notably record the negotiations, several decisions made at the request of the Breton ambassadors, and the provisions intended to enforce the agreements. Research continues to locate the complete text of the capitulation of November 29, 1483. This work requires distinguishing contemporary documents from their transcriptions and subsequent published comments.
A power of negotiation preserved in 1488
The documentation in Simancas also preserves an act from February 12, 1488, under reference PTR,LEG,12,65. The official catalog PARES describes it as a power given by Ferdinand of Aragon to Francisco de Rojas to negotiate a treaty with the Duke of Brittany. This document serves as a direct witness to the diplomatic activity of this period. However, a power of attorney does not, by itself, prove that all the proposed provisions were accepted or executed. This type of distinction is precisely at the heart of the Linked Brittany project. Each document must be studied according to its nature, origin, and historical significance.
Linked Brittany, a method to connect sources
The Linked Brittany project seeks to develop a documentation method based on verifiable references. The aim is to bring together documents concerning the same person, institution, or event without erasing the differences between the sources. Old references, name variations, and degrees of uncertainty must remain visible. Several standards of digital heritage, including IIIF, OAI-PMH, RDF, and CIDOC CRM, are being studied to determine how this approach could become interoperable. The project is still in a phase of research and experimentation. It is not about announcing the existence of a fully completed database.
An approach rooted in European cooperation
These efforts are accompanied by exchanges with historians, heritage institutions, and European networks dedicated to digital humanities. Bretaigne DAO is notably participating in the discussions of the EuropeanaTech community and is continuing talks with Pelagios on the annotation of medieval and modern historical texts. These relationships allow for confronting the difficulties of our corpus with those encountered by other researchers. European cooperation is a central element of Linked Brittany, as the sources necessary for the study of Brittany are preserved in many countries. Their interconnection requires adherence to the archival practices and reuse conditions specific to each institution.
Research intended to remain accessible and verifiable
In parallel with this analysis, Bretaigne DAO is constructing a historical work dedicated to the institutions, diplomacy, and European relations of the Duchy of Brittany. The documents studied must be accompanied by their references, transcriptions, and a critical apparatus allowing the reader to understand what is established and what remains uncertain. The series "Brittany in European Archives," published on ABP, contributes to the same goal. The application for EuroMed2026 represents an additional step in this documentary approach. Regardless of the decision of the scientific committee, the research and gradual publication of the sources will continue.
Sources and references
Archives départementales de Loire-Atlantique, E 201/7, power of attorney from 1372. SIGILLA notice: https://sigilla.irht.cnrs.fr/194002
Archivo General de Simancas, RGS,LEG,148311,60. RGS,LEG,148312,65. RGS,LEG,148312,237. PTR,LEG,92,5. RGS,LEG,148312,246.
Archivo General de Simancas, PTR,LEG,12,65, February 12, 1488. PARES catalog: https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/2206606
EuroMed2026, international conference on digital cultural heritage: https://euromed2026.eu/
First article in our series on ABP, "In 1483: the agreement between François II and the Catholic Monarchs": https://abp.bzh/la-bretagne-dans-les-archives-europeennes-1-simancas-1483-l-75890
Bretaigne DAO — Linked Brittany
Historical and archival research
https://www.bretaigne.bzh/
