One of the main ‘discoveries’ of Blake and Lloyd is the alleged use of the word Britannia to mean Wales. This was first proposed by John Gwenogvryn Evans and A W Wade-Evans, but not taken up by other historians. They use Asser’s de Rebus Gestis Ælfredi Chapter 14 to suggest that his use of the term stood in opposition to Mercia when describing Offa’s Dyke (uallum magnum inter britanniam atque merciam). This is reasonable enough in this context.
However, the dedication of the work, domino meo uenerabili piissimoque omnium brittanniae insulae christianorum rectori, ælfred, anglorum saxonum regi (‘to my venerable and most pious lord, Alfred, ruler of all the Christians of the Island of Britain, King of the Anglo-Saxons’) reveals another usage. Alfred was in no sense ‘King of Wales’, as Blake and Lloyd’s reading would require, but ‘King of the Anglo-Saxons’; on the other hand, he was ruler of all the Christians living in the island, whether Anglo-Saxon, Welsh or Scottish. This implies some sort of overkingship, not of Wales, but of everything we traditionally think of as ‘Britain’.
Elsewhere, Asser is inconsistent. Sometimes he uses Britannia to mean the whole island of Britain, not just Wales. In Chapter 21, we are told that magna paganorum classis de danubia britanniam aduenit, et in regno orientalium saxonum, quod saxonice ‘east-engle’ dicitur, hiemauit (‘a great fleet of the pagans came from the Danube to Britain and wintered in the kingdom of the East Saxons (sic), which is called East Anglia in English’). We know from the Anglo-Saxon Chronicle (which Asser used as one of his sources for this statement) that the fleet did not attack Wales and that Britannia in this instance must include East Anglia. In Chapter 49, we are told that exanceastre, britannice autem cairuuisc… sita est prope mare meridianum, quod interluit galliam britanniamque (‘Exeter, which is called Cairwisc in Welsh… is situated near the southern sea, which flows between Gaul and Britain’). In Chapter 61, exercitus paganorum, qui in fullonham hiemauerat, britannicam insulam deserens, iterum ultra mare nauigans, ad orientalem franciam perrexit (‘the army of the pagans, which had wintered in Fulham, leaving the British island, made for eastern France, crossing beyond the sea’).
Sometimes, though, he uses it in the more restricted sense, as in Chapter 7, where Æthelwulf britanniam cum burghredo rege adiit (‘went into Wales with King Burhred’). In Chapter 79, speaking of himself, ego quoque a rege aduocatus de occiduis et ultimis britanniae finibus ad saxoniam adueni (‘I was also summoned by the king from the western and farthest ends of Wales and came to England’), although in this instance, he might be thinking of St David’s as being ‘at the western and farthest ends of Britain’ – the phrase is ambiguous. When Asser replied that he could not completely abandon his people, the king suggested that per sex menses mecum fueris et tantundem in britannia (‘you would be with me for six months and in Wales for the same length of time’). He states in Chapter 102 that the king made grants to churches in foreign lands when he was able, these being in britannia et cornubia, gallia, armorica, northanhymbris, et aliquando etiam in hybernia (‘in Wales and Cornwall, Gaul, Brittany, Northumbria and sometimes even in Ireland’).
What we therefore have in Asser is a situation where Britannia has two meanings dependant on context; it can mean ‘the land of the Britons’ (i.e. Wales) or ‘the island of Britain’ (i.e. Great Britain). The case is nowhere near as clear-cut as Blake and Lloyd would wish us to believe.