[MontgomeryPy]

Aka Black Irish: https://en.wikipedia.org/wiki/Black_Irish_(folklore)

[cogogo]

That wikipedia article is pretty clear that it is a myth and there is no genetic evidence of shipwrecked Spanish sailors having children.

[MontgomeryPy]

Yes. There is an Iberian connection that explains Irish folks with dark features, but that would be from Neolithic farmers migrating there 5000 years earlier.

[hibikir]

And you see a similar connection in he other direction in northwestern Spain. Regions with redheads and bagpipes. It's not a majority, but you can see it from families tracking their roots to that area from 700+ years.