The Dolwyddelan Codex
A fictional manuscript grounded in historical possibility
In my novel The Silence of the White Shadow, a codex is discovered at Dolwyddelan Castle in North Wales in 1896. It proposes a formal agreement between Welsh princes and the English Crown, suggesting a relationship that sits uneasily with accepted history and directly contradicts the scholarship of one of the novel’s central figures, Emeritus Professor Arthur Cavendish. Its implications are profound, and for him, deeply unsettling.
The codex is, of course, a figment of my imagination.
Yet the anxieties it provokes are not. They are rooted in the realities of medieval politics and in the uncertainties of nineteenth-century scholarship.
Within the logic of the novel, the Dolwyddelan Codex is imagined to have originated during the principality of Llywelyn ab Iorwerth (Llywelyn the Great), who died in 1240. His authority rested not only on strength of arms, but on diplomacy, legal awareness, and a careful negotiation of power with the English Crown. In this period, power was rarely absolute. It was expressed through obligation, agreement, and language that allowed room for interpretation.
In that context, the document functions as a record of conditional arrangements. Its phrasing is deliberately measured, shaped by a political culture in which parity might still be asserted in form, even where it did not fully exist in practice. Agreements were typically recorded in Latin, the language of law, yet their meaning was never entirely fixed. It depended on how they were translated, understood, and remembered within Welsh legal and cultural traditions.
The danger emerges later, during the reign of Llywelyn ab Gruffudd.
In 1267, under the Treaty of Montgomery, Henry III recognised Llywelyn as Prince of Wales. The agreement appeared to formalise a delicate equilibrium. Llywelyn exercised authority within Wales while acknowledging the overlordship of the English Crown. Such arrangements were not unusual. Medieval sovereignty was layered, negotiated, and often deliberately imprecise.
When Edward I came to the throne in 1272, he initially confirmed this settlement. Relations soon deteriorated. Disputes over homage, tribute, and territorial authority intensified, and Llywelyn’s refusal to attend Edward’s court provided the pretext for intervention.
Following this breakdown, Edward initiated a campaign in 1277 that brought immediate pressure to bear on Welsh authority without yet extinguishing it. Advancing into North Wales with a combination of military force and logistical control, he compelled Llywelyn to submit. The resulting settlement, formalised in the Treaty of Aberconwy, reduced Llywelyn’s territorial power significantly, confining him largely to Gwynedd west of the Conwy, while allowing him to retain his title in a diminished and carefully defined sense.
At this stage, the underlying structure of negotiation remained intact, though increasingly constrained. Authority was no longer balanced, but it had not yet been entirely replaced. The language of agreement still held, even as its terms narrowed.
The events of 1282 marked a decisive change. What began as a regional uprising, led initially by Llywelyn’s brother Dafydd, developed into a broader conflict that drew Llywelyn himself into open resistance. Edward’s response was no longer one of pressure, but of conquest. English forces advanced systematically, and in December of that year Llywelyn was killed at the Battle of Orewin Bridge, near Builth Wells.
With his death, the political framework that had sustained Welsh autonomy collapsed. By 1283, resistance had been extinguished, and the remaining leadership eliminated. In the years that followed, Edward consolidated his control through both administration and architecture, embedding authority in stone as well as in law. The Statute of Rhuddlan in 1284 formalised this transformation, converting a negotiated frontier into a governed territory.
This was most visibly expressed in the great programme of castle-building across North Wales, a network later described as a ‘ring of steel’, including strongholds such as Caernarfon, Conwy, Harlech, and Beaumaris. These were not merely defensive structures, but instruments of domination, asserting control over landscape, movement, and population.
It is within this transition that the significance of ambiguity becomes clear. Before these campaigns, language could sustain a degree of flexibility, allowing competing interpretations to coexist. After them, interpretation itself came increasingly under the control of a single authority. What had once been negotiated could now be defined. In such a world, the survival of an older wording was not merely inconvenient. It was potentially subversive.
The idea of a supplementary manuscript preserving more favourable terms for the Welsh is therefore fictional, but not implausible. Medieval documentation was rarely singular or fixed. Charters were copied, glossed, and reinterpreted. Legal traditions evolved through use as much as through decree. In such a world, the survival of a document capable of sustaining an alternative reading of authority is entirely credible.
It is the nineteenth century that gives this idea its sharper edge.
During the Welsh antiquarian revival, manuscripts became objects of intense scrutiny and, at times, controversy. Collections such as The Myvyrian Archaiology of Wales (1801–1807) sought to gather and preserve the literary and historical record of Wales, while chronicles such as Brut y Tywysogion preserved narratives of medieval Welsh rule. Yet the boundary between preservation and invention was not always clear. Figures such as Iolo Morganwg produced materials later exposed as forgeries, but which nonetheless shaped perceptions of Welsh history and identity.
In such an environment, the meaning of a manuscript extended far beyond its text. Questions of authenticity, translation, and interpretation became entangled with questions of nationhood and legitimacy. As E. H. Carr later observed, historical facts do not speak for themselves. They are selected, arranged, and given meaning by those who interpret them. The past is not simply recovered. It is understood through the concerns of the present.
The Dolwyddelan Codex is invented. But the conditions that make it dangerous are not.
A document whose ambiguity once allowed coexistence could, under a different political order, become evidence of a lost claim. A record intended to stabilise relations could, centuries later, unsettle them.
That is the principle at the heart of this fiction.
The past does not change — but its meaning never stands still.
From the research behind The Silence of the White Shadow