Actually, that makes Wildlings as Picts fit even better, as place name analysis indicates that the Pictish language (Or one of them at least, there may have been an older language used ceremonially, as some presumably Pictish inscriptions are indecipherable) was essentially Brythonic, related to the languages spoken by the Britons who inhabited the rest of Britain, including southern Scotland. So if the Britons are analogous to the First Men, the Wildlings could be inspired by the Picts and still have cultural and genetic ties. The Iron Islands could also be similar to the Hebrides, albeit a little too far South for it to match geographically (But then, they're too far South for the straight Scandinavia-analogue anyway), as Scotland's control of the islands was generally nominal at best, and they were subject to the Norwegian crown as often as they were to the Scottish early on, had many Norse cultural influences (including birlinns, which are a form of galley patterned after longships), they were also led by the Rí Innse Gall, or King of the Isles. The reason I like this comparison is because it seems to fit well time period wise, as the Western Islanders maintained their galleys and so in into the 15th century, making them contemperary with the medieval-esque setting of aSoIaF while the Viking Age had ended fully four hundred years earlier. They were also an island chain, which fits with the Iron Islands being, uh... Islands too.
