The Christianisation of the Nordic Countries
The Christianisation of the Nordic Countries took place between the 8th and 12th centuries. Officially, all of Scandinavia was converted to Christianity by the latter date, though it took more time to die out amongst all people in the region; the Sami people of the far north were not converted until the 18th century (though their religion was not that of Thor and Odin). Denmark was the first to give up Norse paganism (at least officially) when King Harald Bluetooth declared conversion in c.975 AD. Norway followed (after earlier unsuccessful attempts) in the early-10th-century reign of Olaf II.
Sweden was all-but Christian by the 12th century, but Iceland provides more of a conundrum, for whilst its conversion took place in 1000, paganism was initially permitted in private. However, this partially explicates the importance of Iceland to our knowledge of Norse Mythology. Most of the great sources for our knowledge of Norse paganism – not least Snorri – are Icelandic. Iceland was, historically, a very literate country (and still has a strong tradition of reading and writing today) which, in addition to its religious tolerance, made it the perfect place for pagan legends and sagas of heathen heroes to be recorded.
Christianisation was not a pleasant experience for the Nordic countries. As a case in point, the first canonised Scandinavian, Saint Olaf, brutally enforced conversion in Norway by killing those who would not comply. Converting to Christianity was often motivated by practicality and self-interest, rather than an acceptance of its particular truth. Harald Bluetooth, for instance, converted Denmark to maintain his independence from Germany. The Christian missionaries were also well-travelled, well-educated, and well-connected: accepting their faith meant improving trade and diplomatic alliances with the rest of Europe, which was a boon to the seafaring mercantile economies of the North.
As for much of Europe, with Christianity came the death of the old religion. The medieval church was fiercely-intolerant of other faiths and diversions from its dogma and ritual, and so religious subversion was extremely rare. The Christianisation process also required the destruction of temples, carvings, and folk-customs related to paganism, effectively wiping heathenism from the history books. This is why piecing together Norse Mythology is so very difficult; nevertheless, it is miraculous that so much evidence has survived. Though we will never know the precise details of Norse paganism, we can still stare in wonderment at what remains.
Where did we find this stuff? Here are our sources:
Davidson, H. R. Ellis. Viking & Norse Mythology. London: Chancellor, 1996.
Ferguson, Robert. The Hammer and the Cross: A New History of the Vikings. London: Penguin, 2010.
Mortensen, Karl. A Handbook of Norse Mythology. Mineola, NY: Dover Publications, 2011.
Snorri Sturluson. The Prose Edda. Trans. by Jesse L. Byock. London: Penguin, 2006.
The Poetic Edda. Trans. by Carolyne Larrington. Oxford: Oxford World’s Classics, 1996.