Kings and their demesnes · Powys · as at first light, 1 January 1200

Gwenwynwyn

The ambitious ruler of southern Powys, who after the Lord Rhys's death in 1197 set out to lead the Welsh and, in the chronicle's words, to restore their ancient bounds.

In 1197 he lent troops to Maelgwn ap Rhys, took Gruffydd ap Rhys prisoner and handed him to the English, and annexed Arwystli. In 1198 he besieged Painscastle in Elfael, William de Braose's castle, and on 13 August the justiciar Geoffrey FitzPeter's relieving army routed his host. He made his peace with John in 1199. On 1 January 1200 he is weakened but still the strongest prince of mid-Wales.

Who he is

Name
Gwenwynwyn ab Owain Cyfeiliog
Title
Prince (lord) of Powys, southern Powys
Since
1195, when his father Owain Cyfeiliog retired to Strata Marcella (Owain died 1197)
Born
Not pinned (before 1170)
Family
Son of Owain Cyfeiliog, prince and poet. Unmarried on 1 January 1200 as far as is known: his marriage to Margaret Corbet, daughter of Robert Corbet of Caus, is dated 'about 1200' and is not pinned. Their son Gruffudd ap Gwenwynwyn comes later.
Confidence
high

Wikipedia (Gwenwynwyn ab Owain); Lloyd, History of Wales.

Overlord

None in practice; made peace with John in 1199

What it holds

  • Cyfeiliog (Machynlleth), his father's cantref
  • Caereinion (Llanfair), Mechain, Mochnant Uwch Rhaeadr, Llannerch Hudol (Welshpool), Ystrad Marchell and Deuddwr
  • Arwystli (Llanidloes), taken in 1197 (medium confidence)
  • Mawddwy (by kinsmen, not pinned)
  • Whether Cydewain (Newtown) and Ceri (Kerry), between his lands and the March, answer to him or to their own lords on 1 January 1200 is not pinned
  • Patronage of the Cistercian abbey of Strata Marcella (Ystrad Marchell), founded by his father in 1170

How it was acquired

Inheritance from Owain Cyfeiliog (1195); Arwystli by force (1197).

Allies and rivals

Ally of Maelgwn ap Rhys against Gruffydd. Rivals: Llywelyn ap Iorwerth, who sent help at Painscastle but will turn on him in 1202; William de Braose and Roger Mortimer on the March; the Corbets of Caus are about to become in-laws.

How things stand that morning

Holds southern Powys from Pool (Welshpool) and Mathrafal; at peace with John since 1199; his field army was broken in August 1198 and has not been tested since.

Wealth

Cattle, the upper Severn valley and its fords, the Cistercians' wool at Strata Marcella, the trade of Pool with Shrewsbury.

Military

His teulu and the levy of southern Powys; castles at Pool (Domen Castell) and Mathrafal. Roger of Howden reports very heavy Welsh losses at Painscastle (his figure runs to thousands).

Threats

  • Llywelyn of Gwynedd
  • Braose and Mortimer on his southern march
  • The royal castle of Montgomery on the Severn

What the year holds

What happened next, if nothing in play changes it. Each event carries what it depends on and what would stop it.

In 1200

  1. About 1200 (not pinned)Marries Margaret Corbet of Caus and receives the manor of Ashford from the crown.Depends on: Peace with John and the Corbets Stopped by: War on the Shropshire border

Later, on the likely course

  1. August 1202Llywelyn raises an army against him; the clergy make peace.Depends on: Llywelyn's ambition Stopped by: A settlement between them first

Places of note

  • Pool (Domen Castell): His castle and llys by the Severn
  • Mathrafal: Ancient seat of the princes of Powys
  • Strata Marcella: Cistercian abbey of his house

Where the sources disagree

Evidence: The Brut and Howden for 1197-98; his holdings are the standard list of Powys Wenwynwyn's cantrefs.

On the map: Ceri and Cydewain, south of his lands, are left undrawn: who held them on 1 January 1200 is not pinned.

Primary sources for Powys

Chronicles, registers, sagas and inscriptions written in or near 1200 that cover this entry. Each has its own page with editions, translations and where to read it.

  • Annals of Wales, Anonymous (St Davids and other Welsh houses) (10th to 13th centuries; the B and C texts continue to 1286 and 1288). Short Latin annals whose later versions are kept at St Davids and Cistercian houses. Read online
  • Chronicle of the Princes, Anonymous (Welsh translation of a lost Latin chronicle kept at Strata Florida) (Latin original to about 1282, compiled from contemporary annals; Welsh versions about 1300 and later). The native Welsh record of the year. Read online
  • The Journey through Wales; The Description of Wales, Gerald of Wales (Giraldus Cambrensis) (Itinerarium 1191, revised to about 1214; Descriptio 1194). The standing description of Wales a decade before 1200: the cantrefs and their lords, the castles of the March, the bishoprics, the Welsh way of fighting and living, and Gerald's advice on how the Welsh might be conquered and how they might resist. Read online

Sources and studies

  1. Wikipedia: Gwenwynwyn ab Owain
  2. Wikipedia: Painscastle
  3. J. E. Lloyd, A History of Wales (1911), vol. 2 (as cited on Wikipedia)

Last revised 4 November 2026. Published 4 November 2026. Suggest a correction on the OMNIA Discord.