The original inhabitants of North America, who migrated from Asia from about 30,000 years ago. By the time of European colonization, the indigenous population was probably under 900,000, mostly living along the coasts rather than in the barren interior. They lived in small villages which, except in the south-west, were organized round hunting, with agriculture a secondary activity. The overall social organization was that of the tribe and warfare between tribes was endemic. British and French settlers in the north-east forced the Native Americans inland, as did the Spanish in the south-west. The acquisition of horses from Europeans increased the number of nomadic societies on the Great Plains. The major tribes are usually divided geographically, North-eastern Woodland (for example, Algonquin, Delaware, Iroquois, South-east (e.g. Cherokee, Choctaw, Creek, Great Plains (e.g. Blackfoot, Comanche, Dakota), Desert-west (e.g. Apache, Pueblo, Navaho), Far west (e.g. Paiute), Pacific North-west (e.g. Chinook), and Mountain or Plateau (e.g. Nez Percé). The Native people of Canada are the Inuit and of Alaska are the Aleut. The indigenous people of Central and South America are usually called Amerindians.