Maybe you’re right about the Celtic origins of the Picts. I did a quick Wikipedia search just now and couldn’t find any mention of some non-Indo European language. It might be a disproven old theory. I read a long time ago that the Romans described the Picts as being smaller and darker than other Celtic speakers and that they guessed that they had an Iberian origin.
As for the origins of the Scots, I refer you to SunkenCiv.
Thanks harold e. :’)
I believe the builders of Stonehenge are thought to have spoken a non-Indo-European language. There were definitely people living in the British Isles before any Indo-European languages arrived there.
Given the genetic evidence for relationships with people in the Iberian peninsula, perhaps before the Celts arrived there was a language related to something spoken in Spain (either a relative of Basque or some other pre-Roman language of Spain).