This demonstrator was created as part of the development work, between August 2021 and June 2022, of a new version of the open source
visual SPARQL query editor Sparnatural, for which the French Ministry of Culture, the National
Library of France, and the Archives nationales de France have partnered to contract with Sparna, Sparnatural’s lead developer.
This demonstrator, which uses Sparnatural, is the result of an exploratory work on the transition from archival
metadata to data graphs, following the projects of qualitative proof of concept PIAAF
(released in February 2018) and development of the RiC-O Converter
software (version 1.0 released in April 2020). The main challenge of the project was to provide users with a relevant and
accessible research interface to explore an archival metadata graph of significant size, which exploits its nature.
Objectives
The work to develop the current version of Sparnatural was carried out by the project team — i.e. representatives of the three
partner institutions and Sparna — with the aim of providing answers to the following general questions:
- How to value a knowledge graph as a knowledge graph?
(and not behind a faceted search engine or clickable navigation
links)
- How to promote exploratory user interactions (test/error) to discover the data?
- How to reconcile generic conceptual models with the specific points of view of the end users?
From the point of view of the Archives nationales, the demonstrator was to be used in particular:
- to test the evolutions of Sparnatural and thereby contribute to the development work;
- to set up a very first web application making it possible to query and consult a significant part of the institution’s archival
metadata, converted to RDF/RiC-O.
In doing so, the objectives were also:
- to demonstrate that large-scale semantization of “classic” archival metadata is possible, and that this opens up new search
opportunities for users;
- to show what such an operation allows to learn about these metadata;
- to build a methodology and acquire skills on the implementation of Sparnatural, which was likely to be used in other
projects.
This work is part of an overall strategy for the evolution of Archives nationales’ metadata and information system towards better
quality, more accessible metadata and linked entity graphs.
The current content of the demonstrator
The metadata of the Archives nationales de France are today mainly:
- more than 30,000 finding aids (conforming to the XML/EAD 2002 DTD),
- more than 15,400 authority records (conforming to the XML/EAC-CPF schema) on
archival creators,
- vocabularies used to index these files,
to describe about 375 linear km of paper archives of all types, not including natively digital archives. The salle des inventaires virtuelle(online catalog) allows users to search
all of these metadata.
Given this important volume, in the absence of a semantic application such as data.bnf.fr and
given the human and financial resources available, a subset of these metadata had to be selected to feed the Sparnatural
demonstrator.
The data graph production process
The selected metadata have been converted into linked data graphs, compliant to the new Records in Contexts Conceptual Model (RiC-CM) and its
technical transposition, the Records in Contexts-Ontology (RiC-O, version
0.2, published in February 2021).
The conversion was carried out twice. The first iteration was performed in November 2021, the second in May 2022, after learning
various lessons from the first one and from the initial configuration work on the demonstrator.
To convert the XML/EAD and XML/EAC-CPF files, we used the open source software RiC-O Converter, developed for the Archives nationales in 2019
and available on GitHub since April 2020. RiC-O Converter produces RDF files compliant with RiC-O 0.1. The resulting files were
then made compliant with RiC-O 0.2 and slightly enriched or modified by specific scripts written by the Lab. Among the
enrichments and changes made let us mention: the propagation of the provenance relation from the description of each fonds to the
description of all the archival resources included in this fonds, the categorization (with the rico:hasDocumentaryFormType property and the document
type vocabulary) of instances of rico:RecordResource that
can be identified as registers, lists of acts and mentions of acts, and the replacement of association relations between notarial
offices and notaries by more precise membership relations.
The vocabularies and records used to index EAD and EAC-CPF files
have been converted using dedicated scripts, written and used by the Lab.
Finally, once imported into the RDF database
chosen for the demonstrator (currently, an instance of the GraphDB
Standard software, configured in a very simple way), the data graph has been further enriched, in order to create classes
specific to notarial archives and to “populate” these classes by inference. The screenshot below shows an example: these are the
SPARQL queries that were used to add the demoanonto:Repertoire class to the RDF database and to create the instances of this
class. In other words, an ontology extending RiC-O 0.2 was produced and implemented. Even if this work was not essential, it has
greatly facilitated the design of the demonstrator’s configurations and also made it possible to optimize its operation by reducing
the execution time of certain queries.
Example of a SPARQL query to create a class in the graph.
Statistical elements concerning the resulting RDF graph
The graph obtained currently has about 57,9 million RDF triples, including about 37 million inferred triples. We can
therefore already estimate that the RDF graph resulting from the semantization of all metadata from the notarial archives of the
Archives nationales would amount to about 170 million triples. In addition, let us recall that the approximately 4900 finding aids of
the DMC make up 16 % of the total number of 30,000 finding aids. Even if simplistic extrapolations are to be avoided, especially
since these EAD files are among the most indexed and precise in the Archives nationales, it is now proven that semantizing all of
the institution’s XML metadata would produce an extremely massive dataset.
This dataset is the first large-scale semantization operation (in RDF compliant with RiC-O 0.2) carried out by the Archives nationales (and in France as far as we know) of “classic” archival metadata. It should be noted that another less massive dataset
was also released in December 2021 (in a public repository on
GitHub) and that it is also accessible via the SPARQL endpoint of the
ALEGORIA project).
In this dataset, are used, among the components defined in RiC-O 0.2:
- 34 classes (entity categories) out of 106 (48 with inferred triples);
- 25 datatype properties (relations whose target is a string) out of 62 (28 counting inferred triples);
- 79 object properties (relations whose target is an entity) out of 423 (162 with inferred triples).
SPARQL queries executed directly in the SPARQL endpoint of the RDF database, in order to go beyond the limit of 1000 results set
for the Sparnatural interface, give the following counts for the main categories of objects described in the graph:
- 72,665 groups of records (fonds, series, bundles, clients files, etc.);
- 400,570 notarial acts (described to date) within the bundles;
- 104,383 mentions of acts recorded in the registers;
- 3135 registers;
- 13,127 lists of acts within the registers, including 11,670 digitized lists;
- 629,246 persons (including 3,213 persons with an IRI);
- 530 organizations (including 528 with an IRI);
- 15,559 places (including 15,463 with an IRI).
As explained below, if the quantities found for notarial acts, mentions of acts and lists of acts are to be regarded as a good
approximation (given the fairly reliable reasoning that we used to generate the data), the numbers found for persons and registers
are not reliable and can only be considered orders of magnitude. However, these statistics, on their own, show in our opinion the
interest of the technologies used (since it is currently impossible for an end-user to obtain them via the Salle des inventaires
virtuelle, and it is not easy to calculate them for a professional competent in the field of XML technologies). They show above
all, if it is still necessary to prove it, the very richness of these archival holdings.
Partial representation, through a diagram, of the description of a notarial act in the graph.
See also the following page
in the demonstrator: http://rdf.archives-nationales.culture.gouv.fr/trifid/recordResource/041835-c1p6y1e0w26r--183v6ez58hjun.
We will continue to work on this data, as explained below.
You can now access the public repository where we manage the RDF dataset on GitHub: https://github.com/ArchivesNationalesFR/Sparnatural_prototype_data. Do not hesitate to contact us if you have questions
about this data!
The graph exploration interfaces
Choices and design methods
Several Sparnatural configuration options are possible: configuration via a Google spreadsheet or an OWL ontology (see the documentation). The Lab chose to configure the demonstrator via an ontology, with
the help of Sparna, and used Protégé, a free software, to edit the ontology.
Sparnatural class edition in Protégé.
The configuration ontology of a Sparnatural search interface imports and uses components defined in two generic ontologies included
in the source code of the software.
The aim is to specify an ontological model for research and its correspondence with the
classes and properties of the domain ontology.
This approach makes it possible to retain certain categories of objects or
relationships rather than others that are considered secondary to search, to specify new ones to group several existing components
in order to simplify the exploration of the graph or to represent text type nodes, to give them understandable labels in the
language you want, to define a display order for the main entry points, to specify how the target nodes of a relationship are
displayed, to use existing SKOS vocabularies, etc. If you know HTML, the data contained in the graph, the business model used and
its implementation, SPARQL and the OWL language, you can build and develop your interface independently.
The aim for the Lab was therefore to achieve a reasonable compromise between the complexity of the domain model and the need to
produce an understandable and efficient interface for users. It took a long time to achieve the current result, through
successive iterations. Feedback from users during the two workshops held at the end of 2021 were invaluable in this respect and
really guided both the developments of the software and the choices we made.
The design work of the search interfaces also made it possible to test the features developed as part of the Sparnatural evolution
project, including:
- the support of the OPTIONAL clause (which facilitates the discovery, as the granularity and the accuracy of the data are
variable and not determined in advance in a graph of cultural metadata, in particular in a archival metadata graph) — we used this
possibility for many relationships, e.g. ‘has digital surrogate’, ‘has title’, ‘have subject’;
- FILTER NOT EXISTS support (to express the negation of a property) — we also retained this possibility in the same cases as for
OPTIONAL;
- the ability to select values from a tree list (of type thesaurus) — we used this feature to allow selection in the document type
thesaurus;
- the ability to add contextual help (tooltips) — this allowed us to attach to each of the categories of entities usable in
the interface a short definition useful in the context of the project;
- the ability to pre-record queries, in order to guide the user in his first queries;
- the ability to choose the result columns to display — this allows the user to define the contents of the result list as he
wishes, so that he can immediately have textual data (rather than only the URIS of entities that a classic SPARQL query returns by
default), operate sorts and then make an export in CSV format;
- the ability to translate the interface into as many languages as necessary — so far we have been able to deploy the search
interfaces of the Archives nationales demonstrator in French and English.
Results
Warnings
The demonstrator only consists of two search interfaces and this documentation. The Archives nationales, unlike the BnF (with
data.bnf.fr), does not have a website for viewing data graphs. A feature was therefore added to the Sparnatural demonstrator to associate each resulting entity with a page allowing simple consultation of its description (via the Lodview application, which was replaced by Trifid in 2026). This feature is not entirely optimal. Moreover, RDF resources IRIs are
not currently dereferencable; in particular, no webpage is associated with these IRIs, nor can we guarantee the sustainability of
the root segment (http://data.archives-nationales.culture.gouv.fr/).
We take any comments or
suggestions for improvement. We are aware that after the user workshops held at the end of 2021, these interfaces need to be
tested by more users. Just like the RDF queried data, the interfaces are likely to evolve significantly.
The source code of the demonstrator is available in the following repository on GitHub: https://github.com/sparna-git/sparnatural-demonstrateur-an.
A Configuration
The first configuration (A interface) is simple and generalistic; it can almost be applied to any
RiC-O compliant archival dataset, insofar as contextual entities such as archival creators, document subject agents, locations are
indexed. It is a priori rather intended for the discovery of metadata. .
The main categories of objects (classes) defined in the configuration ontology and usable in this first interface are:
- Records (a project-specific class, which gathers all archival resources, thus all instances of the RiC-O RecordResource class, with the exception of finding aids and
authority records);
- Person (which corresponds to rico:Person class);
- Organization (which corresponds to rico:CorporateBody
class);
- Place (which corresponds to rico:Place class);
- Documentary form type (class of SKOS concepts defined in the vocabulary of the document types of the Archives nationales, also
instances of rico:DocumentaryFormType class);
- Subject (class of SKOS concepts defined in the vocabulary of subjects, also instances of rico:Thing class);
- Occupation (class of SKOS concepts defined in the vocabulary of occupations and functions of persons,
also instances of rico:OccupationType class);
- Digital surrogate (the instances of class rico:Instantiation having JPEG format, generated from the daogrp elements of EAD files);
- and other associated ‘entities’, which correspond to literal values of RiC-O datatype properties: date, title, name.
Pre-recorded query in the interface A : inventories after death of goldsmiths in the 17th century
B Configuration
The second configuration (B interface) exploits the specificities of notarial archives. It is a
priori rather adapted to the needs of a person familiar with this universe, archivist or accustomed user. This is the
configuration that has had the greatest number of changes in the history of the project.
In addition to the categories of
objects listed above, this configuration defines and uses new categories of objects, and establishes for these new categories
correspondences with classes of the ontology extending RiC-O mentioned above:
- Record set (which corresponds to rico:RecordSet class),
Notarial register, List of acts, Notarial act, Mention of an act, Reference Code;
- Notarial office, Notarial office number, Notary;
- Parisian district or parish, Street in Paris, Parisian building, Address.
Most of these entities can be used from the beginning of writing a query.
New relationships are also present, for example between notarial office and notaries (Notary is member of Notarial office),
between notaries (Notary has successor or has family relation with Notary), between archival resources (such as
Notarial register includes or mentions Mention of an act or List of acts).
Bilan
The demonstrator as an exploration and research device
The results are very positive in terms of the possibilities for exploring the graph and the new research opportunities offered
by Sparnatural.
Among the main points identified by users during the November 2021 workshops, once the surprise effect
has passed, one can mention the intuitive, flexible and interactive nature of this type of interface, which also requires a
greater intellectual commitment for the user than to fill out a classic search form. The user builds his questionnaire by
choosing among the options available to him and discovers the content of the graph at the same time as he constructs his search;
he’s really taking over. It is also easy for him to go back by undoing a step, then the previous one. Finally, he can share the
executed query or export the results of his search.
We cannot, of course, replace the non-archivist user or the one who does not know the RiC-O data model at all. We just want to
present here an example of the searches that a classic search form in EAD files currently does not allow to do, and which
Sparnatural makes possible. This example is the same as the third pre-recorded query in the B search interface.
Pre-recorded query in the B interface : documentary form types of the notarial actes dated 1848, with their reference codes
In this example, we first see that the entry point is a context entity, which is currently rare in our archival search
interfaces, in which the focus is mostly placed at the outset on archival documents. The query editor then allows you to choose a
category of entity related to document types (here, the choice fell on notarial acts), before going through the graph step by step.
The user is still on the same HTML page, and remains in the context of the construction of a questionnaire (without having to work
on search results in which you would then click on hyperlinks, to find out what to expect). He could thus, for example, also be
interested in the archival creator of the acts (notary or notarial office). Such a question, even if it is not formulated in natural
language, seems to us close to the formulation that a researcher in history might make of it, who would like, for example, to form a
corpus and to get a first idea of it. One of the notable features here is also that the user can, for many relationships, either
select the target precisely, or request all the targets of a given relationship (here, all notarial acts, or all dates), at
least initially. The ability to determine which information is included in the results table, and to have textual values (entity
labels), not just URIs, in this table, is also particularly valuable. Finally, the user can easily modify his questionnaire in
stages, or share the query and save the link in his own files, in order to replay the query later.
The functional limits of the demonstrator are essentially those of Sparnatural. The first, already mentioned above, is that
it is a tool for bulding an exploration and search interface in a knowledge graph, not for displaying the data listed in the result
tables and consulting them. Moreover, the Archives nationales does not yet have a way to de-reference URIs. The HTML page display
feature achieved using Lodview then Trifid, obviously does not replace a real design work of a consultation interface, that could also help
visualize parts of the obtained graph, in line with what the PIAAF prototype proposed
for a much smaller amount of data. This was not the purpose of the work done under this project.
Such a search interface is not, moreover, exclusive of a ‘full text’ search allowing, from the word or expression entered, to have
a list of suggestions giving for each of them the type of entity concerned; or tab-type navigation options (one tab per entity
category) as the PIAAF prototype also offers.
Of course, in addition to these limitations, the dataset used does not provide a homogeneous coverage of the archives of the
first 40 notarial offices: the work of analyzing the notarial acts held within these fonds is continuing at the DMC, as in the other
fonds.
Finally, it should be noted that the demonstrator’s data can be queried directly and remotely; the SPARQL endpoint address is https://sparql.archives-nationales.culture.gouv.fr/archives-notariales/sparql. Since 2026, this SPARQL endpoint has also featured a user interface: https://sparql.archives-nationales.culture.gouv.fr/archives-notariales. You can share the URLs of your queries (by clicking the "Share" button). Lastly, we offer an experimental tool that allows for quick searches based on entity names (the value of the `rdfs:label` property); once a result is selected and dragged into the right-hand window, you can visualize the graph containing that entity (by clicking the icons to the right of the rectangle representing the entity). This tool is available at the following address—currently without accompanying documentation: https://sparql.archives-nationales.culture.gouv.fr/archives-notariales/graph-explorer/.
The RDF graph obtained, an example of large-scale use of RiC-O
The result of this large-scale conversion of XML/EAD and XML/EAC-CPF source data to RDF compliant with RiC-O clearly showed:
- that this conversion is entirely possible without necessarily making any changes to this data;
- that the graph obtained from classic archival metadata of this type will offer all the more different entry points and will
be all the more rich in nodes (in entities of various types) as the source metadata use reference data (authority records,
vocabularies) to describe the contextual entities of the records;
- that, even from well-indexed metadata, such an operation will only use a subset of the RiC-O classes and properties,
which is normal since RiC-O is the technical transposition of an overall conceptual framework;
- that, while employing only a small part of RiC-O, carrying out such a project may encourage, in particular in the case of a
homogeneous archival corpus such as ours, to extend this ontology, which is a very generic international model which cannot
take into account the variety of corpuses or all local specificities and needs.
Such lessons may, in our view, be useful to any institution or team that would consider following the same path. We would of course
be interested in any comparable feedback.
A new perspective on the metadata used
At this early stage of the work on metadata that the demonstrator allows to explore, as we have already mentioned above, thanks
to semantic technologies, we have new quantitative elements on the content of the described archives. We will be able to refine
this mapping in the coming months.
Moreover, as in any project for the production and publication of graphs of linked
entities from pre-existing data, where a more or less significant leap is made in precision, the work on the data and their
exploration as a graph have highlighted problems in the source metadata, although not unknown but so far very little visible and
difficult to quantify. Here we will take two examples.
629 246 people in the graph?
The essentially free indexing, via the element EAD <persname>, of persons (except for 3213 of them with authority records) in
the finding aids processed results in a very large number of entities of the type rico:Person in the graph, about which little is
often known (e.g., we know the occupation of 34 925 of these persons only) and which have not been the subject of aggregation or
identification work. In fact, entities with the same name can be aggregated as a single entity Person in this graph only if there
is absolute certainty or quasi-certainty that it is the same natural person — when, for example, that person is found at about the
same date, with the reference to the same occupation or function (or the same relations with other persons), in the acts of the same
notary or mentioning the same property. This is a very interesting field of investigation. Regardless of the results, there
should be a very large cohort of highly blurred individuals whose numbers are not expected to differ significantly from the initial
number.
3135 registers?
This number is much higher than the observed reality. It results from the fact that in the finding aids treated, there are usually
two descriptions (two EAD <c>elements between which no relationship is currently established), created in two different
finding aids, about the same register: one describes the fonds of a given notary, thus its registers — and sometimes, references to
acts in the registers — and minutes; the other, produced as part of the full digitisation of registers, describes the notary’s
registers as material objects and the lists of acts contained therein. This redundancy is not visible enough in the source metadata
in the Salle des inventaires virtuelle; it is much more so in the RDF graph.
Further analysis has led us to decide to carry out, in the coming months, a test on a representative sample of these finding
aids, of linking or even merging the information they contain, in order to produce, ideally, a single description of each of the
registers. This example is very representative of other situations, related to the long history of the Archives nationales
metadata and the phenomenon of stratification of finding aids.
Other tangible results of the project
Preparing RDF data for the Sparnatural demonstrator served as preliminary work for updating RiC-O Converter, during which the necessary tasks were identified and initially coded. This work saved time for subsequent stages. Indeed, since September 2022, we have worked with Sparna to produce and publish version 2.0 and subsequently version 3.0 of the RiC-O Converter software. This latest version generates RDF data compliant with the most recent version of RiC-O—version 1.1—published in May 2025.
The French translations of the English labels for the RiC-O classes and properties used in the graph—produced during the configuration of the Sparnatural demonstrator—were incorporated into the RiC-O source files. This enabled the ontology to include an initial French translation of these components, which has since been updated.
In conclusion: prospects (section updated in October 2026)
We plan to update the graph data by re-converting the source metadata (which have themselves evolved) in accordance with RiC-O 1.2 in late 2026 or early 2027. We might also include a larger subset of metadata; this could prove particularly useful in the context of the C-PARLA project, in which the Lab and the Department of Minutier Central des Notaires de Paris are
involved. We will likely also need to review the dataset's exact scope at that time, as the reference data currently included within it has—since April 2026—benefited from a dedicated web application and SPARQL endpoint via Garance.
At that time, we will also update the Sparnatural configurations to take advantage of recent developments in the tool, such as the use of SHACL for configuration or the ability to search for and display locations (specifically Paris streets in this instance) on a map.
Finally, the Lab is now able to design a Sparnatural search interface for other datasets. Sparnatural has thus been reused in other research projects—for instance, to explore data from the ORESM project (Works and References of Students, Supôts and Masters of the University of
Paris in the Middle Ages), the web portal for which is expected to launch soon.
The Garance application—used by the Archives nationales to publish semantically structured reference datasets—is also expected to soon feature an advanced search form built using Sparnatural.