Does red hair have its origins in Scandinavia rather than Scotland and Ireland?
Redheads are usually associated with the Celtic countries, but the Vikings were known for their red hair too.
Maybe someone with red hair from England, for example, would probably be much more likely to have Scandinavian ancestry rather than Celtic.
I'd appreciate any insights
The neanderthals were red but they appear to be a different species to us; our dna and theirs does not match. However, as the red gene is very old it probably was in the first Europeans,although always probably in the minority. Europe after the Ice Age was repeopled in the north west/atlantic seaboard from peoples who had sheltered in the mountains of france and Spain. A lot of this geneflow went to ireland and probably became cut off there when the seas welled up and made it an island. Norway is right on the tip of the western seaboard and also received some of this geneflow.Red hair is quite common in the Netherlands too and after Ireland and the British Isles, they got the next largest 'dose' of the genes coming out of the Basque area/Iberia. Although the majority of these early settlers were probably dark haired, some probably carried even earlier dna types associated with the red gene,possibly those with the very old mtdna known as U (Ursula or Europa).
Scotland actually has the most red hair,with Ireland next at 10%.Most Irish have dark brown hair but its estimated 40% carry the red haired gene.You need two people both carrying this gene to have a redheaded child, so the old myths such as 'a blond viking carried off a black haired Irish girl and so they had a red headed baby' are just that, myths.