The Mackenzie River husky breed emerged in the mid-1800s during the demand for larger, stronger sled dogs, and describes several overlapping historical populations of Arctic and sub-Arctic sled dogs originally bred to support fur traders and prospectors. Being a mixture of native sled dogs and European freighting dogs, such as mastiffs, Newfoundland Dogs, Saint Bernard and similar breeds, Mackenzie River huskies were prized for their ability to haul heavy loads long distances in the snow with minimal care.

Only small populations of these dogs still exist due to a significant decline in the 1950s and 60s with the introduction of mechanized Arctic travel in combination with the Canadian government’s attempts to eradicate native dog teams.

See: https://en.wikipedia.org/wiki/Mackenzie_River_husky