Prince Oscar Carl August Bernadotte, Count of Wisborg was a Swedish religious activist, the second son of King Oscar II of Sweden and his consort, Sofia of Nassau. Born as a Prince of Sweden and Norway, he was known as Prince Oscar, Duke of Gotland. However, by marrying contrary to Swedish constitutional requirements, he lost those titles, becoming instead Luxembourgish nobility as Prince Bernadotte and Count of Wisborg.

Duchies in Sweden have been allotted since the 13th century to powerful Swedes, almost always to princes of Sweden and wives of the latter. From the beginning these duchies were often centers of regional power, where their dukes and duchesses had considerable executive authority of their own, under the central power of their kings or queens regnant. Since the reign of King Gustav III the titles have practically been nominal, with which their bearers only rarely have enjoyed any ducal authority, though often maintaining specially selected leisure residences in their provinces and some limited measure of cultural attachment to them.