The Kven people (Finnic ethnic minority in Norway) are mentioned in the travelling accounts of Norwegian seafarer Ohthere in 871 - 99. And a small Kven settlement is shown in The map of Scandinavia by Olaus Magnus from 1539.
My questions are: Would they have been practicing the indigenous pagan religion of Finland prior to converting to christianity or Old Norse religion? When did they convert to Christianity? And would they have been considered "pagan" (hedning) in medieval Norway? I would be greatful for any possible information on this.
Unfortunately, researchers don't agree even whether the Kvens (ON Kvenir) constituted a distinct ethnic entity or whether the Kvens narrated by Orthere's description around 900 was basically the same group as they appeared again in Early Modern texts (Hansen & Olsen 2014: 152-55).
In this context, it is interesting that the Kvens disappeared (almost) entirely from West Norse contemporary sources in the 14th century. The last appearance of them in Fenno-Scandia was 1271 CE (the Icelandic annals record their raiding in Hålogaland, Northern Norway). Wallerström's seminal work indeed suggests that the group with new designation replaced the role that the Kvens had traditionally assumed for centuries around 1300: In his understanding, both the new group of people appeared now in Fenno-Scandia, the Birkarls (birkarlar) and the traditional Kvens were primarily middlemen traders between the hunter-gathering 'Finns' (the Sámi) and outer world (Wallerström 1995: 313f.; Cf, Ibid., 355-57 in English summary), though the former mainly came from Tavastland while the latter was mainly drawn from more general West Finnish peoples.
Swedish rulers began to grant the privilege of trading the Sámi to these Birkarls and/or collecting half-tribute payment (tax) from them in the first half of the 13th century, and both Swedish and Finnish scholar suppose that they came from Scandinavian freeholder (thus upper-rank) peasant elites in northern Gulf of Bothnia, though we have not conducted the prosopographical research on their extensive network extended from Norbotten to southern city merchants like those in Turku and Stockholm, until those of the 16th and 17th century (Cf, Miettinen 2016: 242-50).
If we accept this current popular hypothesis of identifying the Birkarls with late medieval successor of the Kven 'traders', represented by Wallerström, then, the main stream of traders from Sweden-Finland in the 14th century, that is to say, the Birkarls, were no other than Christians (Catholic).
On the other hand, I can say with ease that at least the possibility of Old-Norse religion practitioners can be easily ruled out, as I wrote before in Chances of Nordic pagans in 13th-century Svealand?. Concerning the basic timeline of Christianization in Finland, this previous post of mine in Why is medieval Finland so heavily associated with magic? Are there any grounded explanations for why this is? ([Edited]: corrects the link) might also be at least not totally useless, I hope.
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