The Bishopric of Pomesania (; ) was a Catholic diocese in the Prussian regions of Pomesania and Pogesania, in modern northern Poland until the 16th century, then shortly a Lutheran diocese, and became a Latin titular see.
The former Cathedral and Castle of Pomesanian Cathedral Chapter complex in Kwidzyn is listed as a Historic Monument of Poland.
Catholic diocese
It was founded as one of four Roman Catholic dioceses in Prussia in 1243 by the papal legate William of Modena.
The bishops, whose seat was Riesenburg (Prabuty), ruled one third of diocesan territory as his temporality. The diocesan cathedral chapter met in the fortified cathedral of Marienwerder (Kwidzyn). In the 1280s the Teutonic Order succeeded to impose the simultaneous membership of all capitular canons in the Order thus winning influence in the diocese and in the capitular elections of the bishops. So the temporality of Pomesania's bishop did not develop the status of a prince-bishopric and was ruled as part of Teutonic Prussia. In 1454, the region was incorporated by King Casimir IV Jagiellon into the Kingdom of Poland upon the request of the anti-Teutonic Prussian Confederation. The Bishop and canons of Pomesania pledged allegiance to the Polish King during the incorporation in March 1454 in Kraków. After the subsequent Thirteen Years' War (1454–1466) between Poland and the Teutonic Order, the region was recognized as part of Poland as a fief held by the Teutonic Knights.
Beginning in 1523 during the Protestant Reformation, the diocese was effectively administered by Lutheran bishops until 1587, when the diocese was secularized by the regent of Ducal Prussia, George Frederick.
However the Catholic diocese was only formally suppressed in 1763, having remained vacant since 1524 except for 'temporary' Apostolic administrators since 1601.
The diocesan area outside of Ducal Prussia remained Catholic and on 1601.04.19 joined the Roman Catholic Diocese of Chełmno.
Catholic resident bishops
Ernst, Dominican Order (O.P.) (1248/49– death 1259?60) Albert Friars Minor (O.F.M.) (1259? – death 1285?86) Heinrich (1277/78–1292) (Counter bishop) Heinrich von Pomesanien (1286 – death 1303) Christian (1303.05.16 – death 1306.07.22) Ludeko von Pomesanien = Lutho von Baldersheim (1319.12.03 – death 1321.08.28) Rudolf (1322.03.05 – death 1332) Bertold von Riesenburg (1332 – death 1346.11.28?) Arnold (1347.06.04 – death 1360.01.29?) Nikolaus von Radam (1360.04.20 – death 1376.11.27) Johannes Mönch (1378.02.16 – death 1409.03.07) Johannes Rymann (1409.07.24 – death 1417.09.04) Gerhard Stolpmann (1418.05.09 – death 1427.07.22) Johannes von Mewe = Johann von Heilsberg (1427.10.13 – death 1440.07.18) Kaspar Linke (1440 – death 1463.10.28) Nikolaus II (1464–1466) Wincenty Kiełbasa (1467–1478) Johannes Christiani von Lessen = Johann Christian von Lessen (1480.04.14 – death 1501.04.10) Hiob von Dobeneck (1501–1521), Teutonic order( O.T.) (1501.08.27 – 1521.05.25) ? George of Polentz (1521–1523) Apostolic Administrator Achille Grassi (1521.08.09 – 1523.11.22), also/previously Bishop of Città di Castello (Italy) (1506.02.14 – 1515), created Cardinal-Priest of S. Sisto (1511.03.17 – 1517.07.06), Bishop of Bologna (Italy) (1511.05.30 – 1518.01.08), Camerlengo of Sacred College of Cardinals (1517 – 1518.01.08), transferred Cardinal-Priest of S. Maria in Trastevere (1517.07.06 – death 1523.11.22), also Apostolic Administrator of above diocese Bologna (1518.03.03 – 1523.11.22) Erhard von Queis (apparently no proper papal mandate- cfr. infra) (1523 – 1524)