HRH Charles's 12-Great Grandfather. Poss. Lady Diana's 15-Great Uncle. HM Juan Carlos' 13-Great Grandfather. Philippe of Belgium's 13-Great Grandfather. Grand Duke Henri's 13-Great Grandfather. HM Margrethe II's 12-Great Grandfather. HM Beatrix's 12-Great Grandfather. HM Constantine II's 12-Great Grandfather. HM Carl XVI Gustaf's 12-Great Grandfather. HM Harald V's 12-Great Grandfather. Ksr Wilhelm II's 10-Great Grandfather. Wm. von Bismarck's 9-Great Grandfather.