At least, that is what my best hunch would be.
So were Spanish fishermen. It is known that Basques fished off the Grand Banks millenia ago (and still do so today).
However, I don't think Spain could be responsible for the "Indian" ethnic groups. Basques are very tall and are the tallest men in Europe (oddly enough, the women are among the shortest), have very coarse black hair, and are extremely fair-skinned. I don't think you could find much in common with the average Algonquin.