I have a historical problem but it is not really exclusively Celtic.
I wonder if there is an answer to be had at all.
We've been watching DVDs of "Deadwood" a U.S. series, which I believe is alleged to be historically reasonably accurate and I am suspicious of quite a lot of the expletives the people use. They sound kind of late 20th Century to me, though I've never been to the U.S.. Definitly not in 1880
The nearest I got was Huck Finn, who said the raft men called one another Bill and Jo, "And used considerable many cuss words." which is not much help and anyway 40 years too soon.
Hard to verify I fear. Did people write down those kind of colloquial expressions 140 years ago one wonders.
Hope this is not too far outside the remit,
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