This is news? I read this over 40 years ago!
Must be it happened in the 9th century then. :’)
I read it originally, hmm, sometime in the 1970s, in a book that *may* have been titled “Eyewitness to History”, otherwise “Witness to History”. Later I read a book with the opposite title, written by a multilingual diplomat present at the wartime Big Three conferences and whatnot.