One of the most influential thinkers in Wales during the 1960s and 1970s was the philosopher J.R. Jones, who invented the term cydymdreiddiad or ‘interpenetration’ to describe the indivisibility, as he saw it, of language, culture and territory. In his influential work on Britishness, Prydeindod, he argued forcefully that there was no such ‘interpenetration’ between Welsh people and the notion of British identity. On the contrary, Britishness, according to Jones, was an invented political category which was imposed from outside, whereas authentic Welsh identity was indissolubly imbricated in the Welsh language and in the culture and geography of Wales. Jones's ideas would have a profound effect both on the developing ideology of Plaid Cymru (the Welsh Nationalist party) and on Cymdeithas yr Iaith Gymraeg (the Welsh Language Society), founded in 1962, as well as on, either directly or indirectly, a number of mid-century Welsh poets in both languages. For English-language poets of Wales, Jones's philosophy was a confirmation of their cultural loss, as expressed in Harri Webb's ‘Colli Iaith’ (Losing a Language), one of the few poems written by Webb in his second language. As John Davies puts it in ‘How to Write Anglo-Welsh Poetry’, the Anglophone poets of the sixties felt the need to ‘apologise for not being able/ to speak Welsh’. Many of these Anglophone poets, in an attempt to make up for their loss, frequently mentioned Welsh words and place names in their poetry; in so doing, they also, paradoxically, drew attention to their state of linguistic and cultural dispossession.

During the same period, the Austrian economist E.F. Schumacher was gaining widespread attention with his philosophical slogan ‘small is beautiful’, which for many seemed to be encapsulated in the small country of Wales: an ‘unviable’ nation-state from an imperial political point of view but one whose independence, advocated by Plaid Cymru, was coming to be seen as increasingly possible. Evidence for this possibility came with the election of the first ever Plaid Cymru MP, Gwynfor Evans, in 1966. Nor is it an accident that Evans was elected in a Carmarthenshire constituency: the west Wales territory of Dylan Thomas's ‘Fern Hill’ and Gwenallt's ‘Rhydcymerau’, the county which many Welsh writers of the period saw as the heartland of an ‘authentic’ Welsh identity.