This order's claim to authority rested on a specific story. William Wynn Westcott said he had come into possession of a manuscript in cipher, that it contained the outlines of a grade system, and that decoding it produced the address of a German adept, Fraulein Anna Sprengel, who granted him a charter to found an English temple.
The cipher manuscripts are real objects and survive. They use a simple substitution alphabet taken from a published sixteenth-century work by Trithemius, which is to say a cipher available to any reader of printed books on the subject, and they contain skeleton outlines of grade rituals. Their paper has been examined; the watermarks are consistent with the 1809 date some accounts assign, but paper can be used long after manufacture and the writing is what matters. The most likely author on present evidence is Kenneth Mackenzie, a Masonic scholar in Westcott's own circle who died in 1886.
The Sprengel correspondence is a different matter. Ellic Howe examined the letters and reported that their German is not the German of a native speaker, that it contains errors of a kind an English writer with textbook German would make, and that no independent trace of the woman has ever been found. No German order of the name she is said to have represented can be documented. The correspondence ends conveniently, with a reported death, at the point where further contact would have been expected.
The conclusion reached by Howe, and not seriously contested since by R. A. Gilbert or others working on the documents, is that the charter was fabricated, most probably by Westcott, to supply the continental authority that a new English order needed in order to be taken seriously.
What follows from this is more interesting than a simple exposure. The order's founders were not primarily frauds and the system they built was not empty; the ceremonial synthesis assembled from that skeleton, largely by Samuel Liddell Mathers, is the single most influential body of modern Western ritual magic, and most of what later orders practise descends from it. The forgery was in the pedigree, not in the work. That pattern, genuine construction presented as recovered transmission, recurs across this whole subject, and this is the case where the documents survive to prove it.