Medieval cathedrals and the various practices connected to them form an important and complex part of the European cultural heritage. The buildings themselves and their reception into the modern arts ensure their presence within today’s cultural memories and sensibilities. In the mid-twelfth century, a new archbishop’s seat was erected in the Norwegian city of Trondheim (or Nidaros) at the far north of Europe. This interdisciplinary volume, written by scholars of history, architecture, and liturgy, explores the medieval cathedral of Trondheim as a local construction in a European context. As a see of the Western Church, it was set in an international Latinate culture. At the same time, the construction of the building itself and the ritual practices in and around it were influenced by local political, religious, and cultural conditions. The relationship between the physical construction of a cathedral and its function in medieval liturgical and other ritual practices is a topic of wide relevance for architectural and liturgical scholarship. The so-called Ordo Nidrosiensis, the thirteenth-century ordinal of the Province of Nidaros, is an immense help in interpreting the architectural construction and sacred space of Nidaros Cathedral and the Ordo is dealt with in many of the articles. In accordance with general medieval practice, the Nidaros ordinal may be described as international in contents but edited with regard to local considerations.