Any chance the Solutreans and the Basque are the same folks?
Could the eastern US tribes be at least in part remnants of Basque that were pushed out by the Indo-Eurpoers?
That's interesing, I don't believe the Basques were in Iberia when the Romans conquered it. The Solutreans were however in western Europe (and on the continental shelf, now submerged) between 23,000 and 16,000 BC; there's a gap between their *known* presence there and the apparent rise of a similar stone age toolkit in eastern North America. But again, at least part, and probably most of their development was on the continental shelf.