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Dyfed, kingdom of

Dyfed, kingdom of (kingdom of Demetia). The land of the Demetae people at the time of the Roman invasions. Throughout its history, this fertile region of south-west Wales has absorbed external influences—Irish, English, Norman, and Flemish—and changed its ethnic character. The kingdom may have been founded by Irish immigrants, the Deisi, in post-Roman times; its royal dynasty lasted until Llywarch ap Hyfaidd's death (904), when his daughter's husband Hywel Dda, son of the king of neighbouring Seisyllwg, succeeded; Dyfed then became part of the larger Deheubarth. Norman raiders arrived from the north-east in 1073–4, and ten years later Pembroke's fortress was built; thereafter, Dyfed was gradually replaced by several marcher lordships. The memory of Dyfed survived, not least in the Welsh prose tales, the Mabinogi, which were published in English translation in the 19th cent.

Ralph Alan Griffiths

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