There is a reason the indians in western Canada were sparsely populated, and had no technology to speak of. They had no time to delve into science, their entire aim was to stay warm and find food. The surveyors found them wandering aimlessly, starving and often bailed them out, even then. The romantic idea today that they were a proud culture is an enormous myth. They were always on the edge of starvation and freezing. The modified history books would have you think the indians bailed out the explorers, but not a chance. White men had guns, the wheel, horses. The indians had two long poles, wolf/dogs, and flint.

As far as the pioneers, it is not that difficult. Fire. Fur. Adaptability. When it is cold, you do adapt well over time as you get acclimatized. A Texan panhandle fellow, would have trouble up here in winter. But most of the pioneers came from Europe anyway, and  while the winter there is less brutally long, and less intense in temperature, they found it easy enough to adapt. They also had to WORK back then, which heated one up. Today it is -30, and I fed my sheep. I found it was lovely once I got working and pitching hay. In fact I broke a sweat, with a pair of jeans and a chore jacket with a t shirt underneath, in a windchill of below -40.

I wonder more how they survived the heat of the south, quite honestly. It is easier to make a place warm in winter, than to cool off a house before A/C.