A study, 1973-1974, by Ffred Ffransis of a treatise, in Welsh, by John David Rhys (Siôn Dafydd Rhys) on early British history. It comprises a transcript of the text from Peniarth 118, pp. 731-864 (originally typed on stencils, now duplicated by NLW) and a draft introduction, corrected by R. Geraint Gruffydd, with an appendix containing a transcript of a shorter genealogical treatise by Siôn Dafydd Rhys from BM Cotton Faustina E II, ff. 258-72b.