Rhydderch ap Iestyn

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Rhydderch ap Iestyn

Death: circa 1033 (49-67)
Immediate Family:

Son of Iestyn ab Owain, King Of Glywiyssing
Father of Caradog ap Rhydderch and Gruffudd ap Rhydderch

Managed by: Steven Mitchell Ferry
Last Updated:

About Rhydderch ap Iestyn

Please see Darrell Wolcott: The Battle of Mynydd Carn; http://www.ancientwalesstudies.org/id35.html. (Steven Ferry, May 26, 2020.)

Please see Darrell Wolcott: Two Families Headed by a Rhydderch ap Iestyn; http://www.ancientwalesstudies.org/id212.html. (Steven Ferry, July 18, 2020.)

Please see Darrell Wolcott: King of England Mediates Welsh Dispute; http://www.ancientwalesstudies.org/id228.html. (Steven Ferry, August 21, 2020.)

Please see Darrell Wolcott: The 'Next Heir' of Morgan of Caerleon; http://www.ancientwalesstudies.org/id214.html. (Steven Ferry, September 18, 2020.)

Articles that deal with these conflated lines:


Rhydderch ap Iestyn (died 1033) was king of Gwent and Morgannwg in south Wales and later took over the kingdom of Deheubarth and controlled Powys.

Comparatively little has been recorded about Rhydderch ab Iestyn in the annals. He appears to have originally been ruler of Gwent and Morgannwg, where his son later continued to have his power base. When Llywelyn ap Seisyll, king of Gwynedd and Deheubarth died unexpectedly in 1023, Rhydderch was able to seize Deheubarth, apparently by force of arms. In 1033 Rhydderch is recorded by Brut y Tywysogion as having been slain by the Irish, but with no explanation of the circumstances.

The kingdom of Deheubarth returned to the original dynasty in the form of Hywel ab Edwin and his brother Maredudd. A battle between Hywel and his brother and the sons of Rhydderch is recorded the following year. In 1045 Rhydderch's son, Gruffydd ap Rhydderch was able to seize Deheubarth from Gruffydd ap Llywelyn and held it for ten years until Gruffydd regained it.


The first in this line was RHYDDERCH ap IESTYN, whose origins are unknown but who came to power in Glamorgan, as we saw in Welsh Princes 1-2. By 1023 he was strong enough to seize control of Deheubarth from the descendants of HYWEL DDA, but he died in 1033, killed by the Irish (Maund pp.61-2, J.Davies p.99). His son GRUFFUDD ap RHYDDERCH was unable to hold on to his lands, and it was not until 1045 that he had sufficient control of Glamorgan and Monmouthshire to recapture his father’s place in Deheubarth. He resisted the Danes and attacked the English border, but he was defeated and killed by Gruffudd ap Llywelyn in 1055.

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William Jenkins Rees, in his "Lives of the Cambro British Saints," gives a clear and logical explanation of Rhydderch's parentage -- see https://books.google.com/books?id=BNgyAQAAMAAJ&pg=PA654&dq=rhydderc...


Must have perished after 1033:

....Rhydderch ap Iestyn, who was king of Deheubarth from 1023 to 1033.

Davies, John. A History of Wales (Kindle Locations 1709-1710). Penguin Books Ltd. Kindle Edition.

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