Search online for ‘kings of Cornwall’ and you’ll find impressive lists of Cornish kings in its period of independence and even afterwards down to the 1000s. The only problem is that most of these kings reside only as names in ambiguous Welsh genealogical lists. Although resting on earlier but now lost texts, these bare roll calls of names were compiled 600 to 800 years later than the people they listed were supposed to have lived, although no actual dates are provided in the lists either. The apparently complete line of kings from the 400s to the 900s (at least) results from a combination of wishful thinking, modelling Cornwall (and/or Dumnonia) on English or later Welsh kingdoms, and an impatience with ambiguity.
We can be sure about just three kings, who were named by contemporaries. The first was Constantine, described by the British chronicler Gildas around 540 as the ‘whelp of the unclean lioness of Damnonia’ and in a later Welsh source as Custennyn Gorneu (Constantine of Cornwall). The second was Gerent, named by the cleric Aldhelm, the abbot of Malmesbury. He wrote to ‘King Gerent … of the western kingdom’ around 700 calling on him to bring his clergy into line with English (and Roman) practice. The third king was Doniert, whose death by drowning in 875 was noted in the Welsh Annals and who is commemorated by a contemporary memorial stone on the southern edge of Bodmin Moor.
The rest are just names, tantalisingly and teasingly flitting insubstantially through the centuries. Instead of desperately searching for Cornish kings to fill the gaps between the above three, perhaps we should seek guidance from Brittany. There, it’s been argued that between the 600s and 900s there was ‘no clear hierarchy of lordship’ and no ‘permanent kingly presence’.
Cornwall was culturally close to, some might argue virtually indistinct from, Brittany at this period. If Brittany only had intermittent kings, thrown up by emergencies, then perhaps Cornwall did too. Gerent in 700 looks to be a classic candidate for a temporary spokesman required at a time of crisis to negotiate with hostile neighbours.
Long live the king? You have to find him first.
For more on this see chapters 2 and 4 of my Cornwall’s First Golden Age.