There are, from time to time, some articles or speeches which address a common misconception hardly related to linguistics, namely that of Basque being ‘the oldest language’.
Firstly, let me say that I (as many others) like the Basque language specially because of its peculiarity: it is one of those strange language isolates that can be found in some corners of the world, having resisted the linguistic battle of those unending cultural wars that contact between different human societies usually generate. In this very case, the language resisted the spread of Indo-European dialects in Western Europe, just as Uralic resisted mainly in the North, and Caucasian languages did in the East. It is, so to speak, a European linguistic anomaly, as it could be said of Andorra, San Marino or Liechtenstein, if we were talking about the history of European states’ formation.
1. Basque as Europe’s oldest language: Europe’s oldest written language, as far as I know, is Minoan, possibly a language isolate of Crete (and not a Proto-Greek dialect), spoken before the Mycenaean invasion; and that only if we don’t believe that the Vinča-Tordos script or other known scripts were writing systems at all. Europe’s oldest attested language, with strong basis on archaelogical and linguistic findings combined, is of course Proto-Indo-European. That doesn’t mean that Indo-European is the oldest language, though, but only that it is the farthest we can go back in the prehistory of languages, with the linguistic (glottochronology) and archaeological (kurgan hypothesis) findings we have today.
2. Basque as Europe’s oldest non-Indo-European language: again, Minoan is the oldest, non-Indo-European language known to have been written within the European subcontinent; archaeologically attested, I guess, it could be argued that a hundred different non-Indo-European languages were spoken (or even written) at a very old time – some want to trace languages back into Palaeolithic! -, in this or that territory, because of this or that hypothetical cultural continuity found. Even if there were scientific basis to justify them, those cultural continuities obviously wouldn’t imply an ethnic or linguistic continuity; at least none we can ever demonstrate beyond a reasonable doubt.
3. Basque as Spain’s oldest language: we can only talk about a Basque ‘ethnic group’ and basque-related toponyms, specially in Aquitania, since the first Roman invasions, thanks to the writings of Roman historian Strabo, who lived around the beginnings of our Era. Before those writings we only know that, apart from the Vasconians, the (also non-IE) Iberians and the (mainly IE) Celtiberians, Celts and Lusitanians inhabited what is today Spain. Then, if Proto-Indo-European is attested well before that Roman invasion and (knowing about the Celtic migrations’ timeline) if the Lusitanians were really, as suggested, Celtic-like tribes who migrated before them from central Europe – where Italo-Celtic speaking tribes lived – to the South West, then they are the oldest proven people of Spain. That, again, does not mean that any language is ‘oldest’ than others, as such exactness about the origin of a language is impossible to ascertain without a time machine; it is just to prove how wrong the general assuption about Basque is, to the extent that not only the discussion is in itself absurd, but also the common arguments used.
4. Basque as Spain’s oldest non-Indo-European language: again, if we are going to use myths (like some Paleolithic linguistic continuity theories), we should first look at those old written records that talk about Tartessos, a region located in present-day Western Andalusia, where the oldest non-IE attested language of Spain was spoken, Tartessian, possibly an Iberian dialect. We could also talk about Phoenician as a non-Indo-European language of some very old Spanish ports.
5. Basque as Spain’s oldest living language: this is a better approach to the matter, but still far from solving it. Clearly No: Spain’s oldest (attested) living languages are exactly all the Indo-European ones. The history of Spanish, Catalan and Galician (through Latin) can be traced back thousands of years, into its probable pre-Proto-Indo-European origin in the Russian steppes, near present-day Ukraine. Because Basque is only one language, its history cannot be extrapolated anywhere back from Strabo’s short description about the Vasconians; before him, it can only be speculated, not proven.
6. Basque as Spain’s oldest living indigenous language: still better than 5., but also wrong. What we could say is that, ‘since the Roman Invasion, Basque is the only living indigenous language of Spain‘ – that is because we don’t actually know if Basque was really indigenous (i.e. not resulting from migrations) to Spain, or if their speakers – or maybe only the language – arrived to the Pyrenees just before the Romans, maybe from Africa or Eastern Europe. What we do know is that Indo-European dialects didn’t originate in Spain, but we don’t know anything about the origins of the Basque language.
However, point 6. is also wrong, as today’s Basque language is not the same as the old Basque (or Aquitanian) language; in fact, if today’s Basque is a probable dialect of the attested primitive Aquitanian language, is it not Latin also a dialect of Indo-European? or, still better, is it not Latin a dialect of the Italo-Celtic Indo-European dialectal group of Central Europe? And isn’t Italo-Celtic still spoken in Spain, in the form of different modern dialects, like Spanish, Catalan or Galician? Now, if the answer is yes, then Basque cannot even be considered the oldest living indigenous language of Spain since the Roman invasion, as Italo-Celtic – in the form of Lusitanian, Celtic and Latin – could be considered the oldest language really attested, and therefore modern Indo-European languages of Spain could also be considered indigenous.
7. Basque as Spain’s oldest living non-Indo-European language: nope. Arabic, Hebrew, Chinese and other Spanish immigrants’ languages can be traced back well before Basque, and they are also non-Indo-European.
8. Basque as Spain’s oldest living indigenous non-Indo-European language: yes, that’s true. It is tautological, though, as Basque is the only living non-Indo-European language of Spain, so it is necessarily also ‘the oldest’ one.
As a conclusion, not being able to use the above descriptions, one could be tempted to promote it saying that Basque is not related to any other language. This is obviously untrue. Basque hasn’t any known linguistic relative; that does not mean that it isn’t actually related to any language or language family, whether dead or alive. In fact, what many romantics believe is the panacea of the Basque language – namely, the lack of proofs on its origin, history and linguistic relationships – is exactly what makes its study in historical linguistics somehow boring: if there are no known languages related to Basque – with which its evolution could be compared -, but only a linear history from Aquitanian to modern Basque through some mediaeval texts, then the study of the language history is done for the most part. What remains open is just a huge historical linguistic vacuum before the Roman sources, usually filled up with speculation.