| Jurisdiction: | Diocese |
| Samland | |
| Latin: | Dioecesis Sambiensis |
| Coat: | Herb diecezji sambijskiej.svg |
| Province: | Riga |
| Denomination: | Roman Catholic |
| Rite: | Latin Rite |
| Established: | 1243 |
| Cathedral: | Königsberg Cathedral |
The Diocese of Samland (Sambia) (German: Bistum Samland, Polish: Diecezja sambijska) was a Latin Church diocese of the Catholic Church in Samland (Sambia) in medieval Prussia. It was founded in 1243 by papal legate William of Modena. Its seat was Königsberg, until 1523 the episcopal residence was in Fischhausen. The bishopric became Lutheran in the 16th century during the Protestant Reformation and was eventually dissolved following the establishment of Ducal Prussia, a Protestant vassal duchy of the Kingdom of Poland.
The territory of the defunct bishopric of Samland came nominally under the jurisdiction of the Roman Catholic bishopric of Warmia in the 17th century, and the title of bishop of Samland was occasionally used by Warmian bishops.[1] From 1617 to 1773, the Bishops of Warmia were the Catholic Apostolic administrators of Sambia. In 1821 Pope Pius VII formally dissolved the Diocese, and merged its territory with the Diocese of Warmia. Most of the area of the medieval bishopric of Sambia became a part of the Russian Kaliningrad Oblast in 1945 and is now under the jurisdiction of the Roman Catholic Archdiocese of Moscow. A small section around the town of Gołdap became again a part of Poland and maintains its ties to the Archdiocese of Warmia, being administered by its suffragan diocese of Ełk.Samland cathedral chapter was established in Königsberg in 1285 and was dissolved in the 16th century together with the bishopric. In 1989, it was re-established as the Sambian Collegiate Chapter (Sambian Co-Cathedral Chapter since 1992) in Gołdap.