The Vikings’ Conversion to Christianity

“Ansgar Preaches the Christian Doctrine in Sweden” by Hugo Hamilton (1830)

The traditional tales of the Vikings’ conversion to Christianity are sleek dramas full of zealous missionary saints, kings, and clerics who Christianize entire populations in a few heroic actions that are hardly short of miracles. As is the case with most medieval hagiography (a genre focused on recounting the lives of saints and other holy men and women), the historical reality seems to have been much humbler and more mundane. In the words of historian Richard Fletcher, “we may be confident that the conversion of Scandinavia was gradual, piecemeal, muddled and undisciplined.”[1]

In this article, we’ll explore the real process by which the Norse switched their religious allegiance from their ancestral paganism to Christianity. First, let’s look at the general characteristics that defined the Christianization process, and then move on to consider the specifics of how this transformation occurred in the main Norse countries and colonies of the Viking Age (roughly the years 793 to 1066).

Since the Norse had always been in contact with other parts of Europe through trade, travel, and war, they had encountered Christians both abroad and in their own homelands for centuries before the start of the Viking Age.[2] Small populations of Christians lived in Scandinavia’s coastal trade towns.[3] Thus, the Vikings certainly had some familiarity with Christianity before the first missionary ever set foot on their shores.

In fact, many of the Norse had incorporated aspects of Christianity into their own personal religiosity before the official conversion got underway.[4] The tenth-century historian Widukind of Corvey tells us that some pre-conversion Danes believed “that Christ certainly was a god, but claimed that other gods were greater than he, since they revealed themselves through greater signs and omens.”[5]

In Denmark and Sweden, remarkable Viking Age soapstone molds for making pendants have been discovered by archaeologists – remarkable because the molds contained spaces for making both cross pendants and Thor’s hammer pendants, side by side.[6][7] Archaeology also furnishes us with examples of people who were buried with both symbols, including the grave of a ninth-century woman in Hedeby (Denmark) and that of an eleventh-century Norseman in western Finland.[8][9]

The Gosforth Cross in St. Mary’s churchyard in Cumbria

When the Vikings settled in already-Christian lands such as England, Scotland, and Ireland, they tended to readily adopt the religious modes of the local inhabitants.[10] As with their counterparts back in Scandinavia, this led to a hybrid religiosity with elements of both paganism and Christianity.

A particularly striking example of this is the so-called Gosforth Cross, which was erected in a churchyard in the early tenth century in Viking-occupied England. While clearly a Christian monument, its elaborate carvings nevertheless contain illustrations of episodes from pagan Norse myth.[11]

Vidar steps into the mouth of Fenrir during Ragnarok; detail from the Gosforth Cross

Another depiction of this intriguing religious fluidity comes from the medieval Old Norse pseudo-historical writings. According to the twelfth-century Landnámabók (“Book of Settlements”), one of the first Norse settlers to arrive in Iceland in the mid-to-late ninth century was a man named Helgi the Lean. During Helgi’s voyage to Iceland, he called upon Thor for protection, as he often did when he found himself in an especially tricky, trying situation. Yet Helgi had been baptized and thought of himself as a Christian, and when he landed safely on the shores of that new country, he named the settlement he founded Kristsnes, “Christ’s Headland.” It’s impossible to know whether or not Helgi actually existed, but the fact that such characters existed in the popular Norse imagination is telling, especially when compared with the other evidence for the often-ambiguous religious identities of the period.[12]

All of this is to say that, in the words of historian Anders Winroth, “Most Scandinavians of the conversion era did not accept Christianity as a readymade package of beliefs and practices; instead, they accepted a few ideas at a time.”[13] Conversion was a slow process that unfolded over the course of several centuries and many, many generations. The Norse were partially Christian before the formal conversion began, and they remained partially pagan long after it had been officially completed.

Formal conversion, therefore, wasn’t really a matter of introducing Christianity to peoples who were unfamiliar with it, but rather of insisting that peoples who had already integrated some Christian practices and beliefs into their own traditions had to give up paganism altogether and embrace only Christianity.[14] (Needless to say, that insistence was seldom rigorously heeded.)

The official conversion of the Vikings – the process by which the institutions of the church were established in their lands and certain rudiments of Christian belief, practice, and identity became customary or obligatory – mainly took place during the tenth and eleventh centuries.[15]

Each Scandinavian country, province, or locality has its legendary missionary who is credited with more or less singlehandedly converting the populace. They brought the people to the new faith through a bottom-up process like the one modeled in the gospels, where Jesus and his disciples go around and convert the common people directly. In terms of historicity, these accounts are almost exactly backwards. Generally speaking, rulers were the first to be officially converted, and then Christianity “trickled down” to their subjects.[16]

The Christianization of the Norse countries didn’t happen in a vacuum; it was part of a broader trend of Europeanization that Norse societies were undergoing at the time. Formerly, they had been part of a barbarian fringe of Europe rather than “proper” Europeans in the eyes of their southerly neighbors. But during the second half of the Viking Age, they came to adopt many of the staples of European culture and civilization, which brought them into the “proper” European fold.[17] In addition to Christianity, these changes included the adoption of writing (beyond the nominal writing system that runes had provided), the growth of a political system based on kings rather than chieftains, and various smaller modifications of the Vikings’ legal and cultural frameworks.

And why did the Vikings convert to Christianity? What motivated them to give up much of their traditional religion in favor of a new one? Of course, it’s impossible for us to know what was in the hearts and minds of the specific individuals involved. Surely some cases involved genuine religious convictions; it would be superficial and reductionistic to assume otherwise.[18] However, it seems that the majority of conversions occurred largely, and perhaps entirely, for the sake of the tangible, practical advantages that the new religion brought with it.[19]

Recall Widukind’s description of the Danes quoted above: they professed “that Christ certainly was a god, but claimed that other gods were greater than he, since they revealed themselves through greater signs and omens.” The pagan Norse worshiped the gods that they believed were the most powerful and could therefore bring them the best fortunes in this life. Pagan piety had a reciprocal, transactional character that assumed that if one did right in the eyes of a deity – offering sacrifices and prayers, maintaining the sanctity of his or her holy sites, etc. – then the deity would reward such piety with worldly prosperity. There was no doctrine of salvation that would have undergirded the practice of spirituality for its own sake, apart from any earthly benefits it might bring. Thus, the spiritual tended to be seen as a means of achieving natural human ends, and the Norse judged their gods on the basis of the criterion “What can this god do for me?” (It’s arguable that this is how most people from all over the world, pagan, Christian, or otherwise, have always viewed their deities, but such a question is far beyond the scope of this present piece.)

The Norse judged the Christian god according to the same standard. Conversion was therefore predominantly a means of becoming convinced that the Christian god could bring more benefits than the previous gods could – or, at the very least, that he could bring enough benefits to merit being worshiped alongside the established gods.

According to the traditional legends about the conversion process, missionaries often persuaded the people of the extreme power of the Christian god by performing fantastical miracles in his name, feats which always led to a great number of conversions.[20] Needless to say, it’s impossible to determine whether or not there’s any historical truth in such accounts. What we can say, however, is that the Norse seem to have become convinced of the might of the Christian god largely through more down-to-earth political and economic means.[21]

Viking rulers – who, as we’ve noted, were generally the first to formally convert to Christianity – wanted to forge alliances with the powerful Christian kingdoms to the south so as to consolidate their own power. The kings of those southerly kingdoms, in turn, were happy to oblige, as this enabled them to turn former enemies into pacified friends.[22] Viking kings also found that “the document-based church administration was unsurpassed and utterly useful to rule and administer a kingdom.”[23]

After the Viking rulers converted, the nobility followed suit in order to win or maintain the ruler’s favor. Then came the common people, who likewise wanted and needed to stay in the good graces of their superiors. In any case, the acceptance of Christianity (or at least the basics of its outward, formal aspects) was eventually made obligatory for all.[24]

Merchants and traders had an additional incentive to convert: Christians were more comfortable trading with other Christians than with pagans, so being a Christian gave a trader an advantage.[25]

Thus, the conversion of the Vikings to Christianity was primarily a peaceful, voluntary affair.[26] However, there may have been some notable exceptions to this, which we’ll examine below as we now turn to the specifics of the conversion process in each of the Scandinavian countries and the Viking colonies of the North Atlantic.

Denmark

“Ansgar” by Siegfried Detlev Bendixen (1826)

According to the traditional narrative of Denmark’s conversion, Christianization was first and foremost the work of a man named Ansgar (or Anskar), the first archbishop of Hamburg-Bremen in Germany. Ansgar was credited with having converted Denmark, starting with the king. Along the way, he founded churches, and even traveled to Sweden to attempt to convert the Swedes at the invitation of that country’s king. This story comes from the pens of clerics employed by the archbishopric of Hamburg-Bremen, who were motivated by the political desire to claim ecclesiastical authority over Scandinavia. Unsurprisingly, much of this story consists of exaggerations or outright fabrications.[27]

Here’s what actually happened, as far as we can tell:

The first attempt to convert the Danes – or any of the Scandinavians – was made by the Franks in the early ninth century. Under Charlemagne’s leadership, the Frankish kingdom had recently conquered Saxony, the land immediately south of Denmark, and had brought the Saxons into the Christian faith through an exceptionally rapid and violent process – a stark contrast to the gradual, peaceful transition that occurred in most other parts of Europe.[28]

Ansgar was sent north to begin converting the Danes. His only clear success was the conversion of Harald Klak, one of the competitors for the kingship of Denmark, in 810. But the conversion of “King” Harald meant little, because Harald was forced to flee Denmark when the power dynamics in the country shifted against him. He lived the rest of his life in the Frankish Empire, supported by a pension from the emperor.[29][30]

In the ensuing decades, Frankish missionaries sent to convert Danish rulers failed, but along the way converted enough of the populace that a few churches were built and the rudiments of an ecclesiastical structure were put in place.[31]

The first “proper” Danish king to become a Christian was Harald Gormsson, whose nickname was Harald Bluetooth. Harald ruled in the middle of the tenth century, and allegedly adopted the new religion after witnessing a Christian priest from Germany (but not from Hamburg-Bremen) hold a hot iron in his hand without suffering the merest burn. This miracle – and/or the political advantages mentioned above – persuaded him of the power of the Christian god, so he accepted baptism.[32] In or around the year 965, Denmark officially became a Christian country.[33] Harald Bluetooth was the first of a long and unbroken line of Christian kings of Denmark.[34]

Norway

“Olaf Tryggvason’s Arrival in Norway” by Peter Nicolai Arbo (1860)

By the tenth century, there was already a significant Christian presence in Norway. Some of the chieftains who ruled parts of the country were Christian, as were some of their followers. There was even a bishop in Norway from the 960s onward.[35]

During this period, there were no kings who ruled over the entire territory that we now call “Norway.” A “king of Norway” in the tenth century meant a ruler who only controlled some large part of the country, and who had subdued the local chieftains who formerly held sway there.[36]

The first “king of Norway” in that sense was Hákon Aðalsteinsfostri (“Hakon the Foster-son of Athalstein”), who ruled from about 935 to 960. Hakon had been baptized (as his name implies; to be someone’s “foster-son” in this context meant to have been baptized by that person), and established much of the initial ecclesiastical infrastructure in Norway. He doesn’t seem to have particularly bothered pagan worship along the way; he just set up the new system in its midst.[37]

After a lapse during which the country was without a king, the next king in Norway was Olaf Tryggvason, whose turbulent, savage reign lasted a mere four years (995-999).[38] Before becoming king, Olaf had been a leader of Viking raids in England. In the early 990s, the English King Ethelred offered Olaf a very large sum of money in return for a promise to never return to England to raid. Olaf accepted Ethelred’s offer. To seal the deal and to impart spiritual force to it, Ethelred baptized Olaf, making the Norwegian his foster-son – his spiritual kin.[39]

In 995, Olaf sailed back to Norway loaded with English money to finance an attempt to become king. To do this, he first had to defeat and impose his will upon the chieftains who ruled the various parts of Norway.[40]

Wealth wasn’t the only advantage Olaf had in this fight. Christianity was seen as a prestigious religion that made its devotees more socially and politically powerful through their ties with formidable European kings. This was especially true when there was a direct spiritual “lineage” traceable back to one of those kings, as there was in Olaf’s case. Christianity was therefore an impressive gift that Olaf could offer to those who agreed to fight on his side. His pagan competitors didn’t have anything comparable to offer.[41]

According to the traditional biographies of Olaf, he used Christianity not only as a gift, but also as a weapon. He’s portrayed as an ardent Christianizer who made a habit of destroying pagan holy sites and converting his new subjects with a blade pressed against their throats.[42][43]

To what extent do these legends reflect historical reality? Unfortunately, there’s ultimately no way to know for sure. One can readily argue both sides of the debate. On one hand, this portrayal of Olaf as a zealous missionizing king fits so snugly with the conventions of medieval hagiography that historians can’t help but view it with suspicion. On the other hand, however, Olaf’s motivation for forcible conversion would have been an utterly plausible one: by unifying Norway under Christianity, he would have been furthering his goal of unifying it under him as its Christian king. And by attempting to stamp out paganism in Norway, Olaf would have been eliminating his opponents’ ability to rally people around a sacred motivating factor in their opposition to him.[44] If these stories are largely true, Olaf’s reign would be by far the most prominent exception to the otherwise mostly amicable and accommodating conversion of the Norse.

After another period in which Norway was without a king, Olaf Tryggvason’s distant relative Olaf Haraldsson assumed the throne and ruled from 1015 to 1028.[45] Much like his predecessor, but to a lesser degree, Olaf Haraldsson is said to have destroyed pagan worship sites and imposed hardships on those who refused baptism.[46]

Intriguingly, a runic inscription on a stone raised on the island of Kuli near Trondheim asserts that the stone was placed there at a time when “twelve winters had Christendom been in Norway.” Archaeologists have tentatively proposed, based on additional evidence from the site, that this date would have been 1022 – the middle of the reign of Olaf Haraldsson. What happened in 1022? We don’t know. Perhaps the king made the lands that he ruled formally Christian, or perhaps a local ruler accepted the faith in that year, or perhaps a large amount of the local populace was converted.[47]

Iceland

“Althing in Session” by W. G. Collingwood

Since Iceland was first settled at a time when the Norse were already beginning to convert to Christianity, Iceland was a partially Christian society from the beginning. This was especially the case since many of the early settlers came from Viking colonies in Celtic lands, where most Norse men and women were at least nominally Christians. There would have also been Christians of Celtic stock among the members of their households.[48][49]

The source for the traditional narrative of the official Christianization of Iceland is Ari Thorgilsson’s Íslendingabók (“Book of the Icelanders”), which was written around 1125.[50] The story goes like this:

The formal conversion of Iceland began when King Olaf Tryggvason sent Thangbrand, a German priest, to the island. During the year or so he was in Iceland, he managed to convert some influential people. But Thangbrand killed a few people who had insulted him, and had to flee back to Norway to save his life. When Thangbrand told Olaf what had happened, and gave the opinion that converting Iceland would be quite a difficult task, Olaf flew into a rage and threatened violence against some Icelanders who were living in Norway.

A pair of Christian Icelanders, Gizurr the White and Hjalti Skeggjason, traveled to Norway and talked him out of his plan for vengeance. In return, they agreed to attempt to convert the entire island to the new faith. The pair went to the next meeting of the Althing (the Icelandic governing assembly) and presented the matter to the people. This was in the year 999 or 1000. The island was deeply divided by the matter, and the situation was growing tense. Thorgeirr Thorkelsson, the lawspeaker (the head of the assembly) and a pagan, was called upon to arbitrate the dispute. He left the Althing for a day and a night, during which time he lay under his cloak, possibly undertaking a traditional pagan ritual to obtain visionary insight.

When Thorgeirr emerged in the morning, he proclaimed that if Iceland were to remain one country, it had to unite under one religion, and that religion had to be Christianity. Everyone therefore had to be baptized. However, those who wished to continue being pagans could do so privately.[51][52][53]

We have little basis for determining the historical accuracy of this story.[54] Some of its broadest outlines may be verifiable, in that formal Christianity surely did largely come to Iceland from Norway, and certainly seems to have been overseen by Hamburg-Bremen in Germany, since clergy from that archbishopric were active in both Norway and Iceland in the tenth and eleventh centuries. However, to quote Fletcher once more, the plot itself is probably “too good to be true.” The reality stands to have been more gradual and less dramatic than that.[55]

Sweden

The historical record is unfortunately quiet on when and how the conversion of Sweden occurred. Paganism held out there for an especially long time compared to the rest of Scandinavia, but by the twelfth century, the country was mostly Christian.[56]

According to the eleventh-century historian Adam of Bremen, King Erik the Victorious, who ruled Sweden in the late tenth century, converted to Christianity but eventually fell back into paganism. Erik’s son Olaf, who ruled from roughly 995-1022, seems to have been a Christian, as evidenced by coins minted in his name that bear Christian features. Olaf seems to have founded a bishopric at Skara in western Sweden. Olaf’s son Anund ruled from about 1022 to 1039, and was certainly Christian, since he was given the Christian name James. Adam claims that during Anund’s reign, Christianity was widespread in Sweden. England, Germany (Hamburg-Bremen), and Poland all vied for influence in Sweden’s Christian institutions, such as they were.[57]

Greenland

A reconstruction of Thjodhild’s church at Brattahlid (photo by Hamish Laird)

According to The Saga of Erik the Red, there were Christians among the people whom Erik the Red brought to Greenland to settle it in the late tenth century. In 999, Leif, the son of Erik, was converted to Christianity by Olaf Tryggvason. He sailed to Greenland with a priest to convert the people. Erik himself was initially skeptical, but Thjodhild, Erik’s wife and Leif’s mother, embraced it. She refused to let Erik sleep in the same bed as she until he relented and accepted the new religion, which he eventually did.[58]

Regardless of the historicity of the particulars of this story, a tiny church was indeed built in Brattahlid, Erik’s settlement, in the eleventh century. Adam of Bremen, writing in the 1070s, corroborates the notion that Christianity had reached the Greenlanders and was making inroads among them by that time.[59]

Want to learn more about the Vikings’ conversion to Christianity, and the Vikings in general? My list of The 10 Best Books on the Vikings will surely prove helpful to you.

References:

[1] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 416.

[2] Winroth, Anders. 2014. The Age of the Vikings. p. 200-201.

[3] Roesdahl, Else. 1998. The Vikings. p. 158-159.

[4] Ibid.

[5] Winroth, Anders. 2014. The Age of the Vikings. p. 201.

[6] Ibid. p. 199.

[7] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 373-374.

[8] Ibid.

[9] Winroth, Anders. 2014. The Age of the Vikings. p. 199.

[10] Fell, Christine. 2013. From Odin to Christ. In The Viking World. Edited by James Graham-Campbell. p. 163.

[11] Ibid. p. 162.

[12] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 373.

[13] Winroth, Anders. 2014. The Age of the Vikings. p. 200.

[14] Ibid. p. 201-202.

[15] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 621.

[16] Ibid. p. 622-623.

[17] Ibid. p. 622.

[18] Roesdahl, Else. 1998. The Vikings. p. 160.

[19] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 369-416.

[20] Roesdahl, Else. 1998. The Vikings. p. 161-162.

[21] Winroth, Anders. 2014. The Age of the Vikings. p. 202-203.

[22] Ibid.

[23] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 623.

[24] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 369-416.

[25] Roesdahl, Else. 1998. The Vikings. p. 159.

[26] Ibid. p. 162.

[27] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 623-626.

[28] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity.

[29] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 623.

[30] Winroth, Anders. 2014. The Age of the Vikings. p. 202-203.

[31] Ibid. p. 204.

[32] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 404-405.

[33] Roesdahl, Else. 1998. The Vikings. p. 147.

[34] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 404-405.

[35] Ibid. p. 410.

[36] Ibid.

[37] Roesdahl, Else. 1998. The Vikings. p. 165.

[38] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 410.

[39] Winroth, Anders. 2014. The Age of the Vikings. p. 205-206.

[40] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 410-411.

[41] Winroth, Anders. 2014. The Age of the Vikings. p. 205-207.

[42] Ibid.

[43] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 410-411.

[44] Ibid. p. 378-411.

[45] Ibid. p. 411.

[46] Roesdahl, Else. 1998. The Vikings. p. 165.

[47] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 412.

[48] Ibid. p. 397-398.

[49] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 625.

[50] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 398.

[51] Ibid.

[52] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 624-625.

[53] Fell, Christine. 2013. From Odin to Christ. In The Viking World. Edited by James Graham-Campbell. p. 163-165.

[54] Brink, Stefan. 2012. Christianisation and the Emergence of the Early Church in Scandinavia. In The Viking World. Edited by Stefan Brink and Neil Price. p. 624-625.

[55] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 398-399.

[56] Roesdahl, Else. 1998. The Vikings. p. 166.

[57] Fletcher, Richard. 1999. The Barbarian Conversion: From Paganism to Christianity. p. 412-413.

[58] Ibid. p. 400.

[59] Ibid. p. 401.

The Ultimate Online Guide to Norse Mythology and Religion