Chronology of Catholic Dioceses:Notes on the Diocese of Saare-Lääne / Ösel-Wiek - 1228 / 1560

The Diocese of Saare-Lääne / Ösel-Wiek was established in August 1228, covering the islands of Ösel (Saaremaa), Dagö (Hiiumaa) and Moon (Muhu), and Wiek (Läänemaa) - the western part of the Estonian mainland, as a sovereign principality (prince-bishopric) of the Holy Roman Empire (formally from 1 October 1228). Some parts of bishop's possessions (on the islands and mainland) were given as his fief to the Order of the Swordbrothers.

On 15 April 1560 the Diocese was sold by the last prince-bishop to Denmark, and given as an appanage to the brother of the King of Denmark, Magnus Herzog von Holstein (a Lutheran, elected to Bishop 13 May 1560). By this time, Denmark was Protestant.

Information from Mr. Gerard Lovell
(cf. http://www.vdiest.nl/Europa/estonia.htm )