kingdom · British Isles

Kingdom of Gwrtheyrnion

450 CE – 900 CE (approx.)

Tiny Welsh kingdom between the Wye and the Ithon whose rulers claimed descent from Vortigern, the British ruler blamed for inviting the Saxons.

Origins

Gwrtheyrnion means 'the land of Gwrtheyrn', the Welsh form of Vortigern. The Historia Brittonum, written in 829 or 830, says that after Vortigern's fall his son Pascent was granted Buellt and Gwrtheyrnion by Ambrosius, and that its ruler in the author's day, Fernmail, descended from him. The territory lay around Rhayader in what became Radnorshire.

Rule and society

Almost nothing is known of its government beyond this genealogy. It was a small upland territory of river valleys and hill pasture, often ruled together with the neighbouring Kingdom of Buellt, and its dynasty used its link with Vortigern, whatever its truth, to assert ancient legitimacy.

Decline and legacy

Gwrtheyrnion was absorbed by more powerful Welsh kingdoms, probably in the 10th century, and later formed a cantref of the Middle March between Wye and Severn, held by Welsh and Anglo-Norman lords such as the Mortimers.

Few sources survive for this state; details are uncertain.

Connections (1)

More states of British Isles →

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

Last reviewed October 2026Random state ↻