My Ruminations

I know some Welsh people who absolutely abhor the term 'Cambro-Briton, personally I see nothing wrong with it: We are the Cambro-Britons, then there are the Cumbro-Britons; the Strathclyde Britons; the Cornish Britons; the Bretons and the Bretonans.
These terms are used to distinguish the different Brythonic or British peoples, they have an ancient history and mustn't be confused with the post 1707 name which was appropriated for the new State after the union of Scotland with England. Admittedly the word British has since come to have a new meaning and now includes the English, Scots and even Northern Irish, but that doesn't mean that we who know it to have another meaning from farther back, to the time before Scotland and England existed have to necessarily avoid using it ourselves in its older, truer sense.
P.S.Since perhaps the 6th century B.C. the Greeks knew us by the terms Ppettavia and Bpettuavia (Britain); Bpettavoç (a Briton); and Bpettavlkog (the adjective British: the Romans evolved Britannia; Britannus and Britannicus respectively: all these words derive from the Gallo-Brittonic and are similar to both Priteni, the Britons' term for the Picts, and Prydein, the Welsh word for Britain, and thus the Greeks may have picked up (probably from the Gauls) an insular name that the Britons called themselves or a particular British tribe. At the end of the ancient world and the beginning of the middle ages, it was the British political and ecclesiastical elites who defined Brittonic identity, and defined it, at least in part, by what the Britons were not: namely , Pagan and English. The first unambiguous references to Saxon raids on Britain appear c.400 A.D. King Ine's laws
(c.700) show that Wilisc and Englisc are living side by side in Wessex. In the early Anglo-Saxon laws the old English word Wealh, from whence 'Welsh' derives, could denote either a Briton or a slave. While Cornwall and Brittany maintained some degree of Brittonic culture in the early middle ages, it was Wales that defined medieval 'Britishness'. If we take the end of the Brittonic age to be about 600, the history of Wales proper could be said to begin. The Brittonic languages and myths enjoyed a flowering from the 11th to the 14th centuries. It proved to be the twilight of the Britons before the onset of distinctly Welsh, Cornish and Breton identities. The land through which Dafydd ap Gwilym wandered in the 14th century was where Britannia had become Cymru. Kymry or Cymry made its appearence in the 'Armes Prydein Vawr' composed between 935 and 950 as part of the larger group, 'the Brython' about an alliance of all the Britons (from Wales; Strathclyde; Cornwall and Brittany) rising again together to prevail over the German foreigners who were beginning to dominate the affairs of Britain and one day create England.
With thanks to Christopher A. Snyder and his book 'The Britons' first published 2003 by Blackwell Publishing Ltd.