Rupert's Land was a vast geographic region in Canada and the United States. Controlling this area of land meant control over all northwestern Québec bordering Hudson Bay; all northern Ontario; the entire province of Manitoba; all the land and plains south of the parkland belt of Saskatchewan and Alberta; much of the eastern part of the Northwest Territories and south of the 49th parallel; in the United Sates, much of Minnesota and North Dakota. As the fur trade broke into the Great Plains of the Northwest, it encountered another Native way of life. The traders found the Great Plains Indians using for trade the North American bison, or buffalo. They found that the meat of the buffalo had good flavour and texture. Also, when the meat was dried and properly prepared, it would keep for years. The Indian word for dried and prepared buffalo meat was "pimecan." Pemmican, as traders called it, became the quick energy food for the men of the boat brigades.

British Columbia Archives, PDP01729

Different Native tribes called the plains of the Northwest home. There were Cree, Blackfoot and some bands of Plains Stoney or Assiniboine. Also, in the mid-nineteenth century a few bands of the Sioux came north from the Dakota territory, at the same time the U.S. government was attempting to segregate Natives into that area. The Cree were the largest group; in 1871, they numbered an estimated 7,000. To the southwest of the Cree were their old enemies, the Blackfoot tribes, who roamed into United States territories from what is now southern Alberta. The Blackfoot accounted for about 4,000, and other tribes accounted for some 5,000 more.

The Plains Cree were the most willing to accept the fur traders. The Plains Cree were nomads, meaning they wandered the plains following the buffalo herds to provide for their food and shelter.

John Tod's first contact with the Natives of the North was during his time as a clerk-in-training at Trout Lake Post on the Severn River. One of the first things John Tod had to do was learn the local language, an Indian dialect known as Swampy Cree. Tod's knowledge of the Cree language would serve him well in the future, as it was a language understood throughout the Hudson's Bay Company territory.