HRH Charles's 16-Great Grandfather. HM Juan Carlos' 15-Great Grandfather. Philippe of Belgium's 15-Great Grandfather. HM Manuel II's 15-Great Grandfather. Grand Duke Henri's 15-Great Grandfather. HM Margrethe II's 15-Great Grandfather. HM Beatrix's 15-Great Grandfather. HM Constantine II's 16-Great Grandfather. HM Carl XVI Gustaf's 15-Great Grandfather. HM Harald V's 14-Great Grandfather. Ksr Wilhelm II's 14-Great Grandfather.