kingdom · British Isles

Kingdom of Deheubarth

920 CE – 1197 CE (approx.) · capital Dinefwr

The kingdom of south-west Wales, founded by Hywel Dda and later led by the Lord Rhys, a centre of Welsh law, poetry and resistance to Norman conquest.

Origins

Deheubarth, 'the southern part', was formed around 920 when Hywel Dda united his inheritance of the Kingdom of Seisyllwg with Dyfed. Hywel later also ruled Gwynedd and Powys, and became the only Welsh king to issue coins.

Rule and society

Hywel was credited with codifying Welsh law, the Cyfraith Hywel, which governed inheritance, compensation and status. The kingdom's centre was Dinefwr in the Tywi valley. Norman lords overran much of it after 1093, but Rhys ap Gruffydd, the Lord Rhys, rebuilt its power, held the first recorded eisteddfod at Cardigan in 1176 and patronised Strata Florida Abbey.

Decline and legacy

After the Lord Rhys died in 1197, his sons divided Deheubarth in bitter feuds. Its remnants came under Gwynedd's Principality of Wales, and its lands were absorbed by the English crown after 1283.

Lineage

Kingdom of Dyfed 410 CE – 920 CEKingdom of Brycheiniog 450 CE – 1045 CEKingdom of Seisyllwg 730 CE – 920 CEKingdom of Deheubarth

Connections (1)

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Cite this page
APA
The Epoch Institute. (2026). Kingdom of Deheubarth. In The Epoch Institute States Register. https://the-epoch-institute.org/state/kingdom-of-deheubarth
MLA
“Kingdom of Deheubarth.” The Epoch Institute States Register, The Epoch Institute, 2026, https://the-epoch-institute.org/state/kingdom-of-deheubarth. Accessed .
Chicago
The Epoch Institute. “Kingdom of Deheubarth.” The Epoch Institute States Register. 2026. https://the-epoch-institute.org/state/kingdom-of-deheubarth.
Harvard
The Epoch Institute (2026) ‘Kingdom of Deheubarth’, The Epoch Institute States Register. Available at: https://the-epoch-institute.org/state/kingdom-of-deheubarth (Accessed: ).

Last reviewed October 2026Random state ↻