As creatures of legend go, the Wendigo is perhaps one of the most dreadful. It figures in the lore of Algonquian nations in Canada, such as the Cree. It is chiefly noted for eating people. Its height can vary from 6'-9'. Its skin is black and, though covered with flesh and hair, its form is skeletal. Its heart is made of ice and, only by melting the heart (or possibly beheading) can you kill it. It is a voracious eater but is never sated and has a penchant for cannibalism. It has no lips and it is said to have chewed them off.
It will roll in the sand, thereby acquiring an outer coating which makes it look stone covered. Despite its nakedness, it is never cold.
It may have in origin been a personification of the cold. During wild tempests, Indians feel the Wendigo is abroad and will hide. The suspected presence of a Wendigo in the area has been known to induce a kind of collective hysteria. It is very much associated with the bad weather.
Wendigos are so fierce that, if a male meets a female, they will fight. One will slay the other and devour his/her remains. How, then, do Wendigo numbers become replenished?
The awful belief is that, in times of famine, humans can turn into Wendigos. They will then start eating other humans. The famine is at least normally combined with terrible cold. It has been said that there was a psychotic state induced by such factors which led to persons turning into Wendigos, but this has been disputed.
What is the origin of this belief? I would suggest that the Wendigo was initially a spirit of the intense cold of the region. In times of famine, occasional Indians may have resorted to cannibalism, which is deeply abhorred in Indian culture. Perhaps these cannibals, in self-loathing or for safety from other Indians, took to living in the forests or wild places, which is where the dreadful Wendigo is said to dwell. They may have become predators, giving substance to the legend.