Note 4 — DISSERTATION ON THE BOOK OF THE THREE IMPOSTORS.
Reading edition
I believe that we can conclude from all this, that this little book Tribus famosissimus Nationum Deceptoribus, for that is its true title, was composed after the year 1230 by command of the Emperor Frederick II. in hatred of the Court of Rome: and it is quite apparent that Pierre des Vignes, Secretary to the Emperor, was the author.4