It is generally believed that the ancestors of the Indians and the Inuit (Eskimos) migrated to North America across a land bridge between Siberia and Alaska. The ancestors of the Indians arrived at least 12,000 years ago; those of the Inuit, about 5,000 to 8,000 years ago.

At the time of contact with Europeans in the 16th century, there were about 300,000 Indians and Inuit in what is now Canada. The highest concentrations of Indians were in the St. Lawrence Valley and southern Ontario. The tribes there were of the Iro-quoian language family, and included the Huron, Petun, and Neutral. They had complex, highly organized societies, and had extensive contact with other tribes through trade and kinship, as well as through warfare. Their economy was based on agriculture.

Other areas of Canada, such as the north woods and the plains, were thinly populated. The Indians there had less complex societies and were predominantly food-gatherers. Major tribes in the northeast were Algonquian-speaking and included the Micmac, Algonquin, Montagnais, Ojibway (or Chippewa), and Cree. These tribes lived mainly on plants but also hunted and fished. On the plains, food was obtained by hunting, primarily for buffalo. Tribes here included the Assiniboin (Siouan-speaking), the Plains Cree and Blackfeet (Algonquian), and the Gros Ventre and Sarcee (Athabaskan).

The Indians of the Pacific Coast, such as the Tsimshian, Haida, and Kwakiutl, had economies based on fishing and trade. They developed a complex culture, and were master woodworkers and skilled sailors. The Inuit in the Arctic lived in small, usually family-based, nomadic groups. They moved with the seasons in search of game, mainly caribou and sea mammals.