"The Prince-Bishopric of Basel (Fürstbistum Basel) was a historical feudal state within the Holy Roman Empire, from 1032 ruled by Prince-Bishops, whose seat was at Basel, until 1528 and in Porrentruy until 1792. The final dissolution of the state was declared in 1803 as part of the German Mediatisation." (1)

"Besides the city of Basel itself, it comprised territories now in the Swiss cantons of Basel-Landschaft, Jura, Solothurn and canton of Berne, besides minor territories in nearby portions of southern Germany and eastern France." (1)

Records kept by the bishopric are housed at the Archives de l'ancien Évêché de Bâle in Porrentruy.
 

Notes

1. "Prince-Bishopric of Basel," en.wikipedia.org/wiki/Bishopric_of_Basel (Accessed 2011 Jul 19). Bishopric of Basel, CH.