Cunedda’s bard recited in his elegy for his fallen patron that "There was singing before battle". Cassius Dio tells us “The barbarians (Britons) approached with much shouting mingled with menacing battle songs”.
Dio was writing about Boudica’s army and the bard is describing the gwr hen ogledd- The men of the old north- so famed amongst the Cymry. We can see the practice of the Iceni and Trinovantes noted for 61 AD in the south east of the island was still current in 383 AD among British warriors around the Wall. A continuity if you like.
There had been changes too. In Boudica's time the western edge of Empire was at the northern border of her own polity. When Cunedda roamed, it was, by virtue of client states, on the southern bank of the Firth of Forth.
Boudica was part of a cultural and linguistic continuity that stretched from Ireland to northern Italy and beyond most which had recently been subjugated by Rome. She, famously, was having none of that.
The concept that sovereignty might be associated with a living royal woman is a strong undercurrent in some Irish texts and one that’s clearly pre- Christian. I have often wondered about Boudica, was she somehow a living representation of the Icenian Sovereignty Goddess? Her people certainly reacted to her defilement with a fury that we in this modern age might characterise as religious.
And what of Cartimandua? She ruled in a polity constructed around the goddess Brigantia. Her divine patroness was part of a celestial pair with Brigans, likewise Cartimandua ruled with Venutius. Despite massive Roman intervention Brigantian identity seems to have survived, the men of Bryneich, alongside whom Cunedda fought, and the Brigomaglos who held court on the Post Roman Wall both proclaim their Brigantian antecedents. As of course in a different way does St Brigid. A Brigantian continuity if you wish.
Gildas, many scholars think, characterised Boudica as “an unclean lioness” because she rose against Rome, maybe so. Gildas certainly adhered to Rome but it may be that he additionally did his Christian duty in refuting an individual who symbolised the demonic pagan past. A recent past for Britannia and an active present in neighbouring Ireland and among the Picts.
Post Boudica the Iceni seem to have had a rough time of it. We don’t know how much land was confiscated or how many were enslaved, probably a lot of both. Later, the Iceni, now in the civil zone of the Roman province were granted a civates. Even by the standards of Roman Britain it seems to have been a shoddy place. Yet it tells us something important, enough high status Iceni survived for long enough to be given back a portion of their land by the Imperium. Here too there was some continuity.
Up in the military zone Cunedda, who seems to have been a Late Roman military official, held a court that Boudica, druidic art permitting, would have instantly recognised. Bards sang, Heroes boozed and the loot was shared out. A continuity.