I read your post with interest.  I recently discovered Joseph/Arimathea (38BC-82AD) in my family tree through his daughter Anna.  Her brother is listed as Josephus the historian.  I was really surprised because I was not aware of this line.  Anna was born in Jerusalem as was Joseph and Josephus, but according to the family tree report they migrated to Wales and the family eventually came to the USA in time for the American Revolution.  Information comes from  Royal Line (Adamic Genealogy) Mar 1980, Albert F. Schmuhl;Colombia Ency. (c) 1944.
 
Understand that was many generations ago and Anna married a Welchman.  But if the information is correct, I guess my family counts as one of those whose identity stems from one of the 12 tribes of Israel.
 
However, the English kings and queens had their "royal line" traced back and were desirous of being descendants of the kings of Israel.  Sort of like the Pope and the Catholic Church claiming Peter as the first pope.
 
Just thought it interesting.