There was an hour-long program on NPR probably 10 or 15 years ago at least that went into the possible origins of this term and the rather shaky scholarship that has been used to establish this as a viable minority of some sort.

There was a thread several years earlier than the one Jack linked to and I think I dug up that program name and posted it. I'm not going to try to recreate that source, but you might dig a little further and you'll find more here at Mudcat.

SRS