Nidaros

Nidaros, Niðarós or Niðaróss was the medieval name of Trondheim in Norway, when it was the capital of the country's first Christian kings. It was named for its position at the mouth (Old Norse: óss) of the River Nid (today's Nidelva).

Although the capital was later moved to Oslo, Nidaros remained the centre of Norway's spiritual life until the Protestant Reformation. The archdiocese of Nidaros was separated from Lund in Scania by the papal legate Nicholas Breakspeare in 1152 and the shrine of Saint Olaf in Nidaros Cathedral was Northern Europe's most important pilgrimage site during the Middle Ages. Archbishop Olav Engelbrektsson served as a leader of Norway in attempting to resist the Danish Reformation but was forced into exile by King Christian III in 1537. The archdiocese was abolished and replaced with a Lutheran superintendenture.

The Christianization of Norway was begun by Haakon the Good (d. 961), and carried on by Olaf Trygvesson (d. 1000) and Saint Olaf Haraldsson (d. 1030), two Vikings who had converted and been baptized at Andover in England and at Rouen in Normandy respectively.

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