Poss. HRH Charles's 20-Great Grandfather. HM Juan Carlos' 22-Great Grandfather. Philippe of Belgium's 22-Great Grandfather. Grand Duke Henri's 22-Great Grandfather. HM Margrethe II's 21-Great Grandfather. HM Beatrix's 16-Great Grandfather. Wm. von Bismarck's 13-Great Grandfather. `Red Baron' Richthofen's 15-Great Grandfather.