in “Marriage Patterns in Two Wiltshire Parishes 1754-1914: Geographical Mobility, Consanguinity and Illegitimacy” [opens pdf], catherine linley day found that the average cousin marriage rates for stourton and kilmington parishes between the years of 1800 and 1914 were (pg. 243 – click on chart for LARGER view):
those are really low rates. the total average consangunity (first- AND second-cousin) rate is just 3.9%. going out all the way to include sixth cousins, the cousin marriage rate is still only 9.2%.
“In many cases the husband and wife both came from the same clan. In the Cumbrian parish of Hawkshead, for example, both the bride and groom bore the same last names in 25 percent of all marriages from 1568 to 1704.”
so, up north, cumbrians were marrying their paternal kin twenty-five percent of the time — presumably anywhere from first- to sixth-cousins or even farther out, who knows? but that twenty-five percent only includes paternal kin. who knows how frequently they married maternal kin in addition?
i know, i know. the centuries don’t match so these data sets aren’t really comparable. but trust me — this is a general pattern for england — greater inbreeding in the north and less in the south. i’ll have some follow up posts offering more proof for this phenomenon. promise!
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