A comprehensive review of the origins of the medieval monastery on the island of Munkholmen at the gateway to Trondheim by local historian Eystein M. Andersen has revealed that it was probably King Cnut the Great who founded it around 1030 rather than Norwegian lieutenant Sigurd Ullstreng some 70 years later.

This change in the perceived narrative means that St Mary of Nidarholm, which burned down three times in the Middle Ages, finally and irrevocably in 1531, was Norway's oldest monastery.

Although there is no trace of it today – its remains were used to build a rotunda church and fortify the island, later a prison and a German submarine base – Andersen had access to several sources to back up his assertion.

Outlined in a 74-page document entitled Grunnleggelsen av Nidarholm Mariakloster ('The Foundation of Nidarholm Monastery'), through the auspices of the Royal Norwegian Society of Science and Letters, Andersen's painstakingly compiled research leans on liturgical, archaeological, Norwegian, Icelandic and English documentation, as well as the monastery seal itself.

From execution to coronation

Munkholmen was originally a place of execution. The de facto ruler of Norway in the later 900s, Haakon Sigurdsson, and his associate who murdered him, Tormod Kark, were both decapitated here. 

Their heads were placed on stakes to deter locals in Trondheim from any further rebellion, the island just over a kilometer out to sea and visible from the mainland. Olaf Tryggvason, king of Norway from 995, then founded his seat of government in Trondheim. 

Tryggvason, whose statue towers above central Trondheim today, was instrumental in converting Norway to Christianity. Following the death of his beloved young wife Geira, the grieving king-to-be roamed the British Isles, eventually consulting with a seer in the Scilly Isles. 

Soon afterward, he was baptized in Andover, Hampshire, became remarried to Gyda of Dublin, and was persuaded to return to Norway from his Irish idyll to lead the rebellion against Haakon Sigurdsson.

Tryggvason's Christian influence pervaded much of Norway – before settling in Trondheim, he probably built Norway's first church, Old Moster, on Moster island. Thirty years after Tryggvason, it follows that King Cnut the Great would have chosen the location of Munkholmen for the country's first monastery. 

It was in Trondheim that he claimed the crown of Norway in 1028. The year before, Cnut had traveled to Rome for the coronation of the Holy Roman Emperor that Easter. 

The medieval monastery on the island of Munkholmen has been receiving a lot of expert attention in recent years. Photo: Jelena Safronova / Shutterstock

Which monastery is which?

Moving back to Eystein M. Andersen's research, two medieval sources claim different stories of the monastery's origins. Those in Norwegian-Icelandic suggesting Sigurd Ullstreng as its founder may have had a political agenda to do so. Those written by Englishman Matthew Paris, a Benedictine monk like those who lived here, more credibly suggest Cnut. 

Until now, many have thought that the scribe had confused Nidarholm on Munkholmen with the English Monastery Holm in Norfolk, also founded by Cnut. However, Matthew visited Nidarholm in 1248 and was well aware of the monastery and its history. Other ecclesiastical sources Andersen examined also point to Cnut. 

Again, context is required. When Cnut was crowned king of Norway, across a short stretch of water from Munkholmen in 1028, this made him monarch of a North Sea empire including England and Denmark. 

When his leadership was challenged by Olav Haraldsson, who fell in 1030 at the Battle of Stiklestad north-east of Trondheim, Cnut had him canonized in Trondheim, then called Nidaros, in a declaration of reconciliation. This was the spiritual heartland of Norway, its cathedral built from 1070 onwards on the site of Olav's burial.

The main archaeological investigations on Munkholmen took place in the late 1960s and late 1980s. Re-evaluating these records, once thought to suggest a later foundation, Andersen discovers that no clear conclusion can be drawn from them alone. 

While the rotunda still standing today dates back to the 1600s, the round church with a tower present on the monastery seal is similar to those built before 1050, not after it. 

There were, in fact, more churches in the complex, as archaeologists discovered, while the rotunda, like Nidaros Cathedral, is based upon the same dimensions as the Church of the Holy Sepulchre in Jerusalem, typical of the early Middle Ages.

Further investigation at some point, particularly of the medieval elements within the masonry, will surely reveal more secrets.

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