Which language isolate is spoken in the western Pyrenees?

Basque - Euskara to its speakers - is a language isolate, which means that after two centuries of looking nobody has demonstrated a relationship between it and any other language on Earth. Every other language spoken in Western Europe belongs to the Indo-European family and arrived with it. Basque was already there, and roughly 750,000 people still speak it across the western Pyrenees, on both sides of the Spanish-French border.

It is built on principles that make it hard going for a speaker of its neighbours. It is agglutinative, stacking suffixes where English would use separate words. It is ergative, so the subject of a verb like 'run' is marked differently from the subject of a verb like 'carry'. And a single Basque verb form can agree simultaneously with the subject, the direct object and the indirect object, which is three jobs in one word.

Its ancestor is almost certainly Aquitanian, known from personal names in Roman-era inscriptions in the same corner of the world. Beyond that the proposals - links to Iberian, to Georgian and the Caucasian languages, to Berber - have all failed to convince. One charming claim should be treated carefully: several words for cutting tools are built on the root for stone, which is sometimes offered as proof that the language dates to the Stone Age. Most linguists file that under folk etymology.

It nearly did not survive the twentieth century. Public use was suppressed under Franco, and the language was fragmented into dialects that struggled to understand each other. A standardised written form, Euskara Batua, was hammered out from 1968 by the Basque language academy, and a network of ikastola schools teaching through Basque has since taken the number of young speakers back up.