Geographically, the area I'll be asking about goes from subarctic to arctic climate, with taiga in the southern two-thirds and tundra in the northern third. Past the tundra, there's a pretty solid barrier in the form of slowly-expanding glaciers. In the summer, melt from the glaciers fills a series of tributaries that feed into a main river, that in turn flows south, through warmer lands, and eventually out to sea. In winter, most of the tributaries either freeze over or go dry.
In this area, there's a chiefdom of hunter-gatherer-fishers that lives in a landlocked region defined by one such tributary, the Vrae river. Most of them live in the forested taiga, but there is one major village and a pair of outposts that lie near a glacial lake on the tundra. There are few edible plants in the area, so most sustenence comes from hunting and fishing. They have domestic dogs and a few cultivated medicinal plants, but most everything else is wild.
Magic is limited, so there's no conjuring food and medicine out of the ether, but these people can more easily survive the harsh climate, artificially enhance their senses, and enchant their weapons to aim true, wear more slowly, and the like. Technology is mostly based on leather, bone/antler, and wood tools. There's limited copper, but that's about all as far as metalwork goes since there's just plain no other ores where they are.
My question: How many people can this land support?
Google terms: Hunter-gatherer societies, arctic land fertility, population density of hunter-gatherer tribes, land use for the self-reliant. I've also peeked at a few survivalist websites, but those tend to focus more on small-scale agriculture.
The numbers I've seen have varied from 1 square mile per person, to 10 square miles per person, all the way up to 500 square miles per person, which is really too much of a range to base anything on and hope to get it right.