Frederick II, Holy Roman Emperor, 1194-1250.; Innocent III, Pope, 1160 or 1161-1216.; Honorius III, Pope, -1227.; Gregory IX, Pope, approximately 1170-1241.; Innocent IV, Pope, approximately 1200-1254.; Urban IV, Pope, approximately 1200-1264.; Alexander IV, Pope, -1261.; Eugene IV, Pope, 1383-1447, addressee.