My language, the Basque

Basque is the ancestral language of the Basque people, who inhabit the Basque Country, a region spanning an area in northeastern Spain and southwestern France.
It is classified as a language isolate an isolated language and is the last remaining pre-Indo-European language in Western Europe.

VERY WELL DONE!  I also agree with the other corrections as good options and maybe would be slightly clearer in English.  What you wrote is very correct though and a good way of saying things naturally.

My language, the Basque

Basque is the ancestral language of the Basque people, who inhabit the Basque Country, a region spanning an area in from northeastern Spain and to southwestern France.
It is classified as a separate {or distinct} language isolate and is the last remaining pre-Indo-European language in Western Europe.