The Diocese of Skara (Swedish: Skara stift) is the oldest existing diocese in Sweden. It was originally a Latin bishopric of the Roman Catholic church, but since the Protestant Reformation has been a Lutheran diocese within the Church of Sweden, with its seat in Skara at Skara Cathedral. In 2014, it celebrated its 1000-year anniversary as a full diocese. History. Catholic organisation. The diocese was first founded around 990 CE in Skara, the capital of the country of the Geats in Götaland.
https://en.wikipedia.org/wiki/Diocese_of_Skara