This thesis mainly focuses on the transformation of the metropolitan authority of Nidaros in course of the 13th century, especially between ca. 1215 and 1285, and the expansion of the influence of the archbishop over the North Atlantic.
In the first decades of the thirteenth century, the political and ecclesiastical, or metropolitan authority in Norway was intertwined. The political influence of the king of Norway was a prerequisite for the incorporation of the oversea diocese under the authority of metropolitan of Nidaros.
The increasing attempt of the direct contact between the Papacy and the province of Nidaros, triggered by the legation of the cardinal William of Sabina, urged the archbishop of Nidaros to consider and to strengthen the foundation of his authority, hitherto merely vaguely recognized as a sole representative of the papal authority.
The archbishop of Nidaros showed a considerable interest in the contemporary development of the decretal discourses, i.e. the Canon Law, on the ecclesiastical authority in Europe. He began to make advantage of these discourses in form of a series of the papal privileges, in order to confirm the foundation of his authority. He attempted to get tighter hold of their suffragans, mainly by the control of the episcopal election and the closer communication.
This transformation of the nature of the metropolitan power enabled the archbishop to strengthen his position within the province of Nidaros, more independent of the political influence of the king.