Hamar (HAMARCOPIA), Ancient See of (HAMARENSIS), in Norway, embraced Hedemarken and Christians Amt, and was formed in 1152 out of that of Oslo, when Arnold, Bishop of Gardar, Greenland (1124-52), was appointed first Bishop of Hamar. He began to build the now ruined cathedral of Christ Church, which was completed about the time of Bishop Paul (1232-52). Bishop Thorfinn (1278-82) was exiled and died at Ter Doest in Flanders. Bishop Jorund (1285-86) was transferred to Trondhjem. A provincial council was held in 1380. The last Catholic bishop, Mogens (1513-37), was taken prisoner in his castle at Hamar by Truid Ulfstand, a Danish noble, and sent to Antvorskov in Denmark, where he was mildly treated until his death in 1542. There were at Hamar a cathedral chapter with ten canons, a school, a Dominican Priory of St. Olaf, and a monastery of the Canons Regular of St. Anthony of Vienne.