THE LEGENDARY KINGDOM OF SEISYLLWG
By Darrell Wolcott
The noted Welsh historian, J.E.
Lloyd, when speaking of Ceredigion, asserts "Seisyllt, who was king about 730, embarked on a career of conquest and added
to Ceredigion the three cantrefs of Ystrad Tywy, the whole dominion being henceforth known from the name of its founder as
Seisyllwg". Undoubtedly, Lloyd is referring to the Seisyllt ap Clydog descended from Ceredig ap Cunedda who is cited
in Harleian Ms 3859 as an ancestor of Gwgan ap Meurig.
A look at the sources Lloyd used to
support his statement shows it to be more legendary than real. First, he offers a line from the Mabinogion tale "Pwyll
Lord of Dyfed" which reads "Pryderi (son of Pwyll) ruled the seven cantrefs of Dyfed prosperously, beloved by his country
and by all around him; moreover he conquered the three cantrefs of Ystrad Tywy and the four cantrefs of Ceredigion, and these
are now called the seven cantrefs of Seisyllwg." Never meant to be historical, that tale would date the creation
of Seisyllwg to the late 6th century. It claims Pryderi married a daughter of Gwyn ap Gloyw ap Casnar, an historical
man born c. 540, so Pryderi is placed about c. 560. No explanation is offered for naming the new kingdom "Seisyllwg".
Next, Professor Lloyd cites the writing
of two 19th century men: Basil Jones, author of "Vestages of the Gael in Gwynedd", and Egerton Phillimore, editor of the magazine
"Y Cymmrodor". The latter, in vol xi, was speaking of Cantref Mawr in Ystrad Tywy when he says "In the early times this
cantref belonged to Demetia, or Dyfed, but it was conquered in the 8th century, with two other cantrefi south of the Towy
by or before the time of Seissyll ap Clydog, king of Ceredigion, from whom the district of Ystrad Tywy, comprising the said
three cantrefi, was called, together with Ceredigion, Seissyllwg or Seissyll's land". Phillimore cites the Pwyll
tale in the Mabinogian as his authority for the statement. So he would have it that a king of Ceredigion took Ystrad
Tywy from Dyfed, while the Mabinogion story claims the opposite happened...and the two versions of the creation of Seisyllwg
are separated by two centuries.
The next authority given
by Professor Lloyd is Vol 2 of Aneurin Owens' "Ancient Laws and Institutes of Wales", pp 50. This passage retells the
mythical story of how Maelgwn used a chair composed of waxed wings to remain afloat while men representing the other kingdoms
in Wales all sank when the tide came in, allowing Maelgwn to prove his entitlement to be supreme king. Among the lesser
kings who were bested by his trickery was one representing Seisyllwg. Again, that tale is not historical but claims
there was a kingdom called Seisyllwg as early as c. 525 when Maelgwn came to power.
The final "source" cited
by Lloyd is Triad 14 in series iii. The Series iii triads were composed by Iolo Morgannwg (obit 1868) and were not considered
authentic ancient material by Rachel Bromwich when she published her scholarly work "Trioedd Ynys Prydein". The fact
that Iolo mentioned lands called Seisyllwg is entitled to no weight in our search for historical truth; his other
writings show no inclination to stay with the facts.
Thus, we find little in
the literature beyond the borrowing from a Mabinogion tale and changing the era to suit the new tale being related.
Phillimore and Lloyd date the formation of Seisyllwg to correspond with the estimated reign of an 8th century Ceredigion king
named Seisyllt even though two other tales say it existed 200 years earlier. When viewed alongside other "kingdoms"
named in the Mabinogion, it ceases to belong to history so much as to legend.
If such a consolidation of Ceredigion
and Ystrad Tywy ever took place, it must have dissolved before the year 900; the Brut entry of 872 calls Gwgan ap Meurig "king
of Ceredigion", indicating those lands had their own king independent of Ystrad Tywy. Further, the entry of 807 citing
the death of Arthen (ap Seisyllt) calls him "king of Ceredigion" and this was within one generation of the man who supposedly
One might logically ask, what
difference does it make whether or not there was a kingdom of Seisyllwg in the 9th century? It is crucial to the claim
that Rhodri Mawr "inherited" it from his reputed wife, Angharad ferch Meurig, sister of king Gwgan ap Meurig. Those
who make that claim could not simply say she was the heiress of Ceredigion; Rhodri's supposed seat for that part of his empire
was Dinefwr located in Ystrad Tywy, not Ceredigion. It is certainly beginning to look like his "rule"
in that part of Wales is as bogus as we have shown his rule in Powys to have been. While various medieval and modern
writers assert, as though it were established history, that Cadell ap Rhodri Mawr inherited a vast kingdom in south Wales,
no ancient sources confirm that notion. Professor Lloyd only calls it "most probable" and based on the fact that his
descendants are found in south Wales. But those were also descendants of Cadell's son, Hywel Dda, who did in fact rule
from Dinefwr in Ystrad Tywy. And it was no inheritance from either his father or his grandmother.
Perhaps we should begin at the
inception of this new dynasty, with Merfyn Frych. As the maternal grandson of the last male descended from the First
Gwyedd Dynasty (his mother was Esyllt ferch Cynan Tyndaethwy, an only child), Merfyn came to Anglesey from the Isle of
Man in 816. He forcefully ousted Hywel ap Caradog from the island cantref and sent him back to his patrimony of Rhos. One
would suspect his first order of business was to meet with the heads of other families who had recognized Cynan Tyndaethwy
as their king. After securing their support for his kingship claim, as much by sword-rattling as by any entitlement
via his mother, he would have likely turned his attention to the kingdom of Meirionydd, still ruled by descendents of Meirion
ap Cunedda. Its king was Cynan ap Brochwel ap Ednyfed. We suspect Merfyn Frych was able to bring those lands into
his sphere of influence by agreeing to marry a daughter of Cynan. He was then about 29 years old and unmarried.
We suggest it was Nest ferch Cynan ap Brochwel of Meirionydd whom he married, not the mythical "Nest ferch Cadell ap
Brochwel of Powys". But that Nest was no heiress (Cynan had a son, Cadwaladr) and she brought no land to her husband
or their sons.
When Merfyn died, or was killed,
in 844, his son Rhodri was perhaps 24/26 years old. It is possible that Merfyn's brother Cadrod acted as interim king
until Rhodri attained "full age", but he might have immediately succeeded his father. This was the era of
invasions by both Vikings and Saxons, and Rhodri set out to unite the Welsh Cymri for self-defense. He found both
Caradog Freich Fras ap Hywel of Rhos and Brochwel ap Aeddan of Powys eager to pool their forces to resist the Saxons who,
unlike the Viking sea raiders, sought Welsh lands and not simply lootable valuables. But the kingdom to his south,
Ceredigion, may have been reluctant to lend its warband to the united army proposed by Rhodri. Its king,
Meurig ap Dyfnwal, was directly descended from Ceredig ap Cunedda and his family had fended off for centuries any overtures
to fall under the influence of Gwynedd. Assuring Meurig that his lands would remain as an independent kingdom, Rhodri
Mawr likely secured a military alliance with Ceredigion by marrying Meurig's daughter Angharad. Again,
this marriage brought no lands with it; Meurig had a son, Gwgan.
Medieval writers claim this marriage
was to bring the kingdom of Seisyllwg to Rhodri, when King Gwgan ap Meurig died in 872 without heirs. Not only is
it doubtful there ever was a kingdom of Seisyllwg, we suspect that Einion ap Meurig ap Caradog ap Cloddien
Frych ap Llowarch ap Seisyll ap Eiddon Ddu of a cousin line of Gwgan ap Meurig was a logical member of the
Ceredigion Dynasty to inherit its rule. But Angharad may well have inherited the personal manor of her brother
and father, and it may have been a part of the inheritance of her son Cadell. But whatever lands those may have been,
they were in Ceredigion and not near Dinefwr.
By Angharad ferch
Meurig, Rhodri had at least 3 sons who survived him when he was killed in 878. Anarawd, the eldest, succeeded him as
king of Gwynedd, while Merfyn ap Rhodri was given the lordship of Lleyn and probably the neighboring cantrefi of Eifionydd
and Ardudwy. While the third son, Cadell, would have inherited scattered manors throughout those lands now
ruled by his brothers, if he held any lordship at all we do not know where. Nor do we have any early authority
which cites his marriage; modern writers call her Rheingar but give her no ancestry. By tradition, she supposedly was
a lady of Dinefwr in Ystrad Tywy.
Subsequent events lead
us to identify this lady as probably a sister of Llywarch and Rhodri ap Hyfaidd ap Bleddri; that family had replaced the ruling
Dyfed family when it became extinct in the male line. Owain ap Maredudd ap Tewdos (descended from the ancient Deisi
dynasty of Dyfed) had only a daughter, Tangwystl:
650 Cadwgan ap Caten
(king of Dyfed)
(lord of Ystrad Tywi)
To Cadifor Fawr of c. 1030
(king of Dyfed)
(heiress of Dyfed)
Tangwystl, the heiress of Dyfed,
married an unidentified man called Bleddri. According to the Triads, this man was not a nobleman of Wales.
We prefer to think he was described in that manner simply because no pedigree could be found citing his ancestry. Tangwystl's
father Owain died in 811 when she was but an infant and his brother, Meurig, was not yet of "full age" to become king.
It was most likely a brother-in-law of Owain and Meurig who became the interim king of Dyfed, a man who had married their
sister and was father to Bleddri. If so, then Bleddri and Tangwystl were first-cousins. One logical guess for
the identity of this interim king of Dyfed is Dyfnwallon of Ceredigion. This might explain why historians think a link
existed between Dyfed and Ceredigion; one son of Dyfnwallon became king of Ceredigion and it may have been another who became
king of Dyfed. Thus:
765 Dyfnwallon=====dau f. Maredudd
ap Tewdos 780
830 Gwgan* 835 Angharad
830 Hyfaidd** 840 Aleth
*King of Ceredigion until he died
childless in 872
**King of Dyfed until he died in 893
can now chart the marriage connections which the clan of Rhodri Mawr made with the Ceredigion and Dyfed families:
790 Merfyn Frych
820 Rhodri Mawr========Angharad 835
850 Cadell====Rheingar 865 Llywarch
Elen f. Aleth ap Bleddri 880
Asser's Life of King Alfred says that the sons of Rhodri Mawr were threatening Hyfaidd's lands
so that king submitted to the overlordship of Alfred for protection. Perhaps it was Alfred's idea that two
sons of Rhodri Mawr should marry granddaughters of Bleddri, the first-cousins Rheingar ferch Hyfaidd and Elen ferch Aleth. This
was a common tactic which allowed sons of potential conquerors to obtain lands by marriage rather than by combat.
It would appear that land is all that the
son of Tudwal ap Rhodri obtained in Dyfed, and Tudwal (being lame) expected nothing more. But Cadell wanted
a kingdom the equal of Gwynedd which his elder brother Anarawd ruled. Standing in his way were his brothers-in-law Llywarch
and Rhodri ap Hyfaidd. It is unknown how Llywarch, who became king of Dyfed in 893, met his death in 904 but his brother
Rhodri must have then claimed the kingship.
The Annales Cambriae tell us
in 904 that "Rhodri ap Hyfaidd's head was struck off". That language seems to imply an execution, not merely death
on the battlefield. If he continued the assault on the church of David which Asser says marked the reign of Hyfaidd
his father, it may have given Cadell the opportunity to seek his arrest and execution. But Cadell was now about
55 years old and perhaps in poor health....he died a mere 5 years later. His sons Hywel and Clydog, however, were in
their mid-20's; almost immediately after the last male heir of Dyfed was executed, Hywel Dda ap Cadell married the young
daughter of Llywarch ap Hyfaidd. And this, we believe, was when the clan of Rhodri Mawr first obtained the manor at
Dinefwr. Hywel quickly cowed the other dynastic families of Ceredigion and Dyfed into accepting local lordships
subject to him as king, calling the combined kingdoms (Dyfed and Ceredigion) by the new name "Deheubarth". Initially,
Hywel may have ruled with one or more of his brothers, but in 921 he did homage to King Edward the Elder and can be assumed
to have been in sole control of Deheubarth after the death of Clydog.
Our view, accordingly, is that
"Seisyllwg" or "Seisyll's lands" was no more than Ceredigion; that Dyfed comprised most of what is now called Pembrokeshire
and Carmarthenshire, and that Deheubarth was formed by Hywel Dda by combining the two kingdoms. Moreover, we believe
none of it was ever held by Rhodri Mawr; if Cadell ap Rhodri ever ruled anything from Dinefwr, it was only between
905 and 910.