Some more peoples of the World of Greyhawk for you, though the details are sketchy and I'm not always sure what the closest analogue would be...
"These herders and hunters [i.e., the Chakyik/Tiger Nomads] roam freely across the steppe south of the Burneal, trading with the folk of Ekbir and Perrenland, as well as the Wolf Nomads to the east, and
the Chakji tribes of the northern coast beyond the border of the Black Ice." (Living Greyhawk Gazetteer, 2000, p. 114, emphasis added)
"They [the Chakyik/Tiger Nomads] warred with the
Flan tribes of the Burneal, whom they called the Uirtag, as well as the Guryik people from the Land of Black. Some of the nomads even made settlements along the northern coast near the Burneal. Among them was the last remnant of stray Oeridians who had followed the horde to the northern steppes.
Together they mixed with the tribes of Burneal and the Land of Black Ice to become a distinct people, the Chakji." (ibid, pp. 114-115, emphasis added)
"Little-known Flan savages called the Uirtag dwell in the interior [of the Burneal Forest], living in huts made of green boughs in the brief summer and in burrows dug into the ground during the long, cold winter. A few Chakji tribes on the forests' [sic] western fringe trade with the Tiger Nomads and inhabitants of the Land of Black Ice (see Tiger Nomads)." (ibid, p. 139)
Black Ice, Land of: "At the far edge of the Flanaess is a seemingly endless landscape of blue-black ice, filling the northern horizon beyond the Burneal Forest and Blackmoor. The source of these rolling fields of ebony ice had never been explained.
On the Dramidj coast dwell the Baklunish Gyurik folk; on the Icy Sea side are the Zeai, related to the Ice Barbarians." (ibid, p. 154, emphasis added)
Summary:
The Chakyik (i.e., Tiger Nomads, who are primarily Baklunish with feint Oeridian bloodlines) intermarried with the Uirtag (Flan) and the Gyurik (apparently Baklunish) people from the Land of Black Ice, leading to the emergence of another distinct people--the Chakji.
The Gyurik seem like they might be vaguely Inuit (academics believe the latter are believed to be distantly related to northeastern Siberian migrants).
I am not familiar with any northern indigenous peoples in the real world who took shelter in burrows in winter, so not sure who exactly--if anyone--the Uirtag are modelled after. That said, natural caves or snow caves seem like potentially viable winter habitations for fantastical indigenous peoples (I just don't seem them digging burrows into the ground, for a variety of reasons).
The Zeai can evidently be added to the list of Nordic/Norse analogues.
You may also find this thread of interest:
Canonfire!
