Some of the kingdoms that adjoined Cynwidion seem highly likely, given the evidence, to
have been based on old Roman cities and Roman cantrefs (the equivalent of modern
Caer Luit Coet (Roman Letocetum, modern Wall in southern Staffordshire) was the
place to which the kings of Glastenning
(the Dumnonian sub-kingdom in
It was also the capital of the eastern half of the Kingdom of Pengwern, which apparently consisted of
three sub-kingdoms, governed directly or indirectly by the over-king himself
(there is little evidence to suggest the territory fragmenting in the
seventh century, so its central authority must have retained overall
It is likely that Pengwern had been divided between sons in the Celtic tradition, becoming sub-kingdoms
based perhaps at Caer Guricon (Roman Viroconium, modern Wroxeter just east of Shrewsbury
in Shropshire), Caer Magnis (now Kenchester, just west of Hereford in Herefordshire), and
Caer Luit Coyt.
Caer Guricon has provided the most extensive archaeological evidence for
the survival of the Roman way of life during the fifth to sixth centuries in Midlands Britain.
Nothing is known about the formation of this kingdom, but by 613, the
King of Pengwern was Cyndrwyn Fawr (the Great, although his other nickname was the
Stubborn). Constantine probably ruled in Caer Magnis (and was probably a younger brother), and a
second brother, Morfael ap Glast, was king of Glastenning and gained Caer Luit Coyt in
Cyndrwyn Fawr fought in battle against King Ęthelfirth of Bernicia at the Battle of Caer Legion
(Chester, in Cheshire) in 613 alongside the kings of Gwynedd, Powys and
Dumnonia. It seems he survived the fight to die around 620. The kingdom passed to his son,
Cynddylan, who ruled for around thirty-six years before the kingdom fell in 656.
Cynddylan's capital, Llys Pengwern, is traditionally said to have been
the Saxon foundation of Shrewsbury, but was more likely the Berth at Baschurch, just to
the north. There are indications that there was also an outpost at Din Guricon, the hill
fort on the Wrekin that overlooks Caer Guricon, but such were the incursions of the
Iclinga Angles to the east, and various Saxon groups to the south, that a more
defendable site than the old Roman town was required by this time.
Cynddylan's exploits are remembered in the Marwnad Cynddylan and the Canu Heledd (a cycle of
poems named after Cynddylan's sister, and originally attributed to King Llywarch Hen of South Rheged, erroneously as
it turned out - none of the work of this poet-king has survived).
They tell Heledd's lament at the destruction of the Kingdom of Pengwern, and of Cynddylan and his family.
Cynddylan had been far from idle during his reign, and had made a strong alliance with
Penda of the Mercians. They had
fought together against the invading Northumbrians,
particularly at the Battle of Maes Cogwy (Oswestry, Shropshire) in 642.
Here they were successful, killing their northern enemy, King Oswald. This appears to have brought
Pengwern fourteen years of comparative peace, but in 656, after Penda's death, Oswald's
brother, Oswiu, found his way clear to wreak revenge on Cynddylan. He overran Llys
Pengwern, and the Pengwernian king was brutally hacked down along with several of his brothers.
He was buried at Eglwysseu Bassa (Baschurch, Shropshire) and the Royal Court dispersed
(perhaps returning to the land of its cousins in Gwynedd).
With the territory now undefended and largely in the hands of Oswiu
while he was overlord of the Mercians, western Pengwern was settled by Saxon groups moving
up from the territory of the West Saxons
and the Hwicce.
They made the most of the sudden power gap to found small kingdoms based on Caer Guricon (the modern
name Wroxter has evolved from the Saxon Wrocenset, which itself is a rendering of the
Roman Viroconium) and Caer Magnis (the Magonset
Saxons also derived their name from the former Romano-British name).
By the beginning of the eighth century, the Anglian Mercians had gained overall
control of the region.