ok. moving northwards for a sec … sveeeeeden.
inbreeding (or outbreeding) in scandinavia in the dark ages? who knows? no written records, obviously, except for the odd runic inscription here and there. it’s probably a safe assumption to guess that the scandis were like the germanic tribes and did, indeed, practice some form of endogamous mating — likely some cousins, but who knows which ones and how frequently? we’re not even exactly sure what the marriage practices of the germanic tribes were like and we have some (late in the period) written laws from them.
“The Scandinavian clan or ætt was a social group based on common descent or on the formal acceptance into the group at a þing. [T]he clan was the primary force of security in Norse society, as the clansmen were obliged by honour to avenge one another. The Norse clan was not tied to a certain territory in the same way as a Scottish clan, where the chief owned the territory. The land of the Scandinavian clan was owned by the individuals who had close neighbours from other clans. T he name of the clan was derived from that of its ancestor, often with the addition of an -ung or -ing ending.”
so, there you go.
christianity arrived relatively late way up north so that, while some of the german groups on the continent were already being told not to marry their second-cousins in the 500s, the swedes were still having battles between christians and pagans as late as the 1000s. presumably this meant that more swedes were following their old mating practices rather than the new-fangled christian ones until a much later date — as late as the 1100s maybe. so i would guess that the scandinavians do not have the depth of outbreeding that, say, the english and other north-west european populations have.
fast-forward to the reformation — most of the protestant churches in europe did not ban cousin marriage the way that the roman catholic church had done (and still does with first-cousin marriage). the new churches went with what the bible said, particularly leviticus — and the old testament, having been written by the ancient hebrews, was of course ok with cousin marriage.
the exception to this rule of protestant churches was the swedish luthern church which banned cousin marriage (i believe) right at the start of its foundation in the 1500s until 1680 when one could get a dispensation to marry a first-cousin (but see quote below). so, cousin marriage was, presumably, not practiced by the catholics in sweden and, then, also not practiced once the church there became luthern [pgs. 550 & 552-53]:
“Although strongly Protestant, the Lutheran Church in Sweden initially banned marriages between first cousins throughout the country, but from 1680 a dispensation for first cousin marriage could be granted by the King in Council. The expense involved was, however, a major disincentive and during this period first cousin marriages were rare and principally contracted among the nobility (Alstrom, 1958). After unsuccessful attempts in 1809 and 1823 to remove the requisite fee for first cousin marriage dispensation, it was reduced by the Swedish Riksdag (Parliament) in 1829. Then, after another failed attempt at reform in 1841, in 1844 the Riksdag formally revoked the requirement for royal dispensation, leaving first cousins free to marry should they so desire. The history of consanguineous marriage within Sweden can therefore be conveniently sub-divided into three separate time periods: pre-1680, 1680–1843, and 1844 onwards….
“Prior to the introduction of royal dispensation in 1680, first cousin marriages were very rare in Sweden, since they were not sanctioned by the Lutheran Church (Alstrom, 1958). Thereafter, the prevalence increased nationally to an estimated 0.2% in 1750, 1.0% in 1800 and 1.5% by the mid-19th century. This study also reported a distinct north-south cline, with the highest rates of consanguinity in the more sparsely populated northern regions abutting Finland, that are home to most of the Swedish Saami (Lapp) community. Investigations during the first half of the 20th century, mainly based on first cousin marriages only, confirmed the continuing north-south cline of consanguinity (Fraccaro, 1958), with an upper prevalence of 6.8% first cousin unions in a remote northern parish (Book, 1948), compared to 1.7% and 1.3% first cousin marriages in southern and western rural regions of the country (Book & Mawe, 1955; Larson, 1956).“
so, first-cousin marriage rates in sweden in more modern times:
1750 = 0.2%
1800 = 1.0%
mid-19th c = 1.5%
early-20th c = 1.3%-1.7% (western & southern sweden)
edit: also compare the mid-19th century rate of first-cousin marriage sweden — 1.5% — with the mid-19th century rate for consanguineous marriages (only first-cousin?) amongst protestants in alsace-lorraine — 0.186%. and, amongst catholics in alsace-lorraine — 0.997%.
of course, the swedes could very well having been marrying their second- and third-cousins (spoiler alert: they did), but it’s late now so i’ll take a look at that in another post (hopefully tomorrow).
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