
Mapping the Historic Boundaries of Wales: Commotes and Cantrefs
Understanding the historic administrative boundaries of Wales and how they have changed over time is integral to our understanding of the Welsh landscape. The Royal Commission has developed two digital geospatial layers using late-medieval sources and historic parish boundaries to recreate the boundaries of the commotes (cymydau) and cantrefs (cantrefi) of medieval Wales.
Historic Boundaries of Wales
Future developments will examine how these boundaries have changed over time and map them in further detail. These digital resources will be made freely available to the public as an aid to encouraging research.
This data will be an important addition to our on-line services, particularly the List of Historic Place Names of Wales and The Inventory of Historic Battlefield in Wales.
Commotes of Wales

(cymydau) of Wales, as listed by Gruffudd Hiraethog (d.1564) in NLW Peniarth MS.147.
Cantrefs of Wales

(cantrefi ) of Wales, as listed by Gruffudd Hiraethog (d.1564) in NLW Peniarth MS.147.
18/05/2017
Many thanks for this extremely useful dataset. I am looking at the 2019 shapefiles, and I see three discrepancies between the modern England-Wales border and the eastern extent of the commote/cantref polygons. I don’t know enough about the historic changes in the border to know whether these differences are valid etc, but worth checking. In all cases, these are communities that are within modern Wales, but not included in the commote/cantref shapefiles. Six communities in three parishes, as listed below. I can send maps, if useful. Apologies if this proves to be a wild goose chase! Thanks again, Mike 1.… Read more »
Hi Mike, Thanks for your comment and pointing this out. The discrepancies between the England / Wales border could be caused by two things. Firstly, we used Peniarth 147 which lists the parishes which lists the parishes which were in each Commote, and then by extension which Commotes where in which Cantref. If the parish was missing or not listed, this may have caused the discrepancy. Alternatively, the issue could also have been created from the vector dataset we used. For this project we used Kain and Oliver’s 1851 Parish Record Census data which was vectorised from the 1 inch… Read more »
Any progress on historic parish boundaries?
Hi Kirk, We are currently doing some work on Anglesey and hope to have a new dataset for the island available later in the spring. There is a new project looking at the Marcher Lordships which will be creating new historic boundary datasets that we are also working with, so we should start to see some progress in 2023. As ever, I wish it could be quicker, but we are working on it, in between other commitments, and eventually hope to complete a dataset for township boundaries as well. We are planning an event later in 2023 to look at… Read more »
These maps are really great but I would really like to have a look at what Pen. 147 says.
I’ve not been able to find a transcription of Pen. 147 – has a transcription of the Cantrefi a Chymydau text ever been published, or are there page images available anywhere?
If anyone on the project would be able to point me in the right direction, I’d be extremely grateful. Diolch.
Hi Peter, Thank you for your comment. Here is a link to the transcription of the relevant section of Peniarth 147, the source we used in the datasets https://babel.hathitrust.org/cgi/pt?id=uc1.c026025176&view=1up&seq=967&skin=2021 The datasets were the first attempt to try and create a digital layer of these medieval boundaries and should be considered as a useful draft version, as we have a long way to go fully work this out. It is not a straightforward task. The current historic parish boundary layer needs revision and we need to better understand boundary changes over time. There is not as yet a comprehensive boundary layer… Read more »
You can download the Cantref and Commote boundaries here:
Commotes: http://www.arcgis.com/home/item.html?id=1d4fdb0c96f442558cd796a93ecddc22
Cantrefs: http://www.arcgis.com/home/item.html?id=672d2f121f324cbeadc8580397153a5c
Have downloaded but what sort of software do I need to open it?
Hi Charles, you’ll need some form of GIS software. There are lots of free options available, such as QGIS. Here’s a list of various options: https://gisgeography.com/free-gis-software/
Hi Charles you can access all the Gis related software like Erdas,Envi and ArcGIS and pdf book from Here thanks me later https://cartogeek.com/free-gis-software/
This seems to have all gone quiet about 3 years ago. Is the project still running? Is anyone there to read this?
[…] To view the maps visit https://rcahmw.gov.uk/mapping-the-historic-boundaries-of-wales-commotes-and-cantrefs/. […]
“freely available” is vague. Please can you clarify the licence that will apply to the data, and to your images?
The current page, for example, is labelled “Non-commercial Government Licence” – that does not not meet the definition of an “open licence”.
Hi Andy, we hope to make this data available under an Open Government Licence (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/) which is different to the Non-commercial Government Licence that applies to the content and images on this website.
Seriously guy’s really appreciate this, awesome work
It would make the project more interesting if there was a modern-day overlay that would show people the history of where they live 🙂 I am sure this is possible 🙂
I was thinking exactly the same thing
Very interesting, but you need to improve the resolution to magnify
High resolution and GIS versions of these maps are freely available for consultation via computers within the Royal Commission’s library and search room. We plan for these to be digitally integrated across our web services for further research opportunities in the near future. Photocopies of these maps are available from the Commission’s enquiry service.
I’d be very interested in seeing these maps overlaid on a topographical map. Will these be available as ESRI compatible files?
Hi Paul, we will be enhancing the metadata for this layer over the next month and hope to make it available as a Web Feature Service for use within GIS.