1) As far as I can tell it was a secret technique in some English and French magical circles in the 19th century -- how far back, I don't know. It would still be secret, except that Crowley and Regardie published the details.

2) Yep. There's a proto-LBRP in Eliphas Lévi's Doctrine and Ritual of High Magic -- we'll be getting to it in a few months -- and it's pretty clear that it evolved gradually in English and French occult circles, probably beginning in the 18th century.