Public APIs of the National Archives
Most recently updated: 2023-08-21
The National Archives data platform contains a number of publicly available APIs. These APIs provide read access to open, generally available data.
Metadata harvesting via OAI-PMH
Open Archives Initiative – Protocol for Metadata Harvesting is a protocol for metadata harvesting, i.e. retrieval of metadata for the archival records at the National Archives.
Documentation of metadata harvesting
Viewing digital archival records via IIIF
International Image Interoperability Framework is an API for management of digital media, primarily images but also moving images (video) and sound. The National Archives’ IIIF services provides presentation of images with cropping, scaling etc, playback of video and sound and browsing of media resources.
Documentation of presentation of digital archival records
Search API (beta)
The National Archives Search API is a REST API, giving external systems access to search functions like our Cross Search and provides public information as linked data (Resource Description Framework, RDF ). Presently (summer 2023) the Search API is a beta version.
Linked Data (beta)
The National Archives use Resource Description Framework (RDF) for representing single records, serialzed as RDF/XML and JSON-LD . Mapping the data to RDF is a work in progress, currently incomplete.
Documentation of our linked data
Available archives
OAI-PMH
It is possible to harvest metadata for all approved archives in the National Archives present in NAD. These are also available in the search service. There may be individual series, volumes, etc. in approved archives that are not approved. Metadata for these are excluded from harvesting. Other archival institutions' archives in NAD are not available for OAI-PMH harvesting.
IIIF
Only media with explicit rights statements, pertaining to material which is 110 years or older are available via IIIF. Images from the following datasets in the search service special search facilities are available regardless of rights statements:
- The Main Catalogue of Diplomatarium Suecanum (SDHK)
- Census data, older than 110 years
Road map
In 2023, our plan is to begin the development of an API to search NAD and the National Archives' other major registers and databases. Our intention is that the API should correspond to the search, faceting and sorting possibilities as well as the information content of our Cross Search. We will also begin the development of making records in NAD available as linked data
Our intention is to make these new functionalities available first in simple versions, with first versions perhaps only available for test use, and then gradually update them. No date has yet been set for when the first versions will be available.