As far as 'Lost Tribes' many have marveled at the phenotypic variety on the British Isles. This can be seen in faces like Tom Jones, Inglebert Humperdink, and Cary Grant. They are much swarthier than the faces we typically think of as being "British". I personally wonder if this is part of the mystery of a possible ancient Semitic influence.
King David and King Solomon (from the tribe of Judah) were described as swarthy .....or was that ruddy?
What does ruddy mean?
I believe there are huge numbers of Israelites out there, and they are certainly all shades, but the default lens looking back seems to be quite influenced by politically correct ideas about people today using the old name.
Following are a couple .pdfs that have a bunch of research concerning the possible Israelite origins of the Celts.
Thanks for the uploads!
I have looked at a lot of info over the years including some black Israel information. The evidence I've seen does support Celtic harp players inheriting the tradition and skill from King David.