Quick Question on Sephardic Jews... 

Hello all... i'm not a jewish person but have a great deal of interest in both Israel & Judaism, and have doubts as to the meaning of "sephardic jew"

Wikipedia & other i-net resources have given me the definition most of you will know (from Iberian peninsula, emigrating to the mediteranean region, etc...) but what raised my doubts is something else.

I recently saw a documentary which claimed that Sephardic jews originated from a tribe in a land adjacent to israel (in the north, though i forgot its ancient name). The king/leader of this tribe was deeply impressed with his jewish neighbours and converted himself, as well as all his people, to judaism...

I can find nothing to back this up, and would love any imput you're wishing to provide..

Thank you all,

Hayden