The Fourth World is an extension of the Three-World Model, used variably to refer to
- Sub-populations socially excluded from global society;
- Hunter-gatherer, nomadic, pastoral, and some subsistence farming peoples living beyond the modern industrial norm.
- Sub-populations existing in a First World country, but with the living standards of those of a Third World, or developing country.
Fourth World follows the First World, Second World, and Third World classification of nation-state status; however, unlike the former categories, Fourth World is not spatially bounded, and is usually used to refer to size and shape which does not map onto citizenship in a specific nation-state. It can denote nations without a sovereign state, emphasising the non-recognition and exclusion of ethnically- and religiously-defined peoples from the politico-economic world system, e.g. the Romani people worldwide, the Sami, pre-First World War Ashkenazi Jews in the Pale of Settlement, the Assyrians, and the Kurds in the Middle East, Pashtun throughout Afghanistan and Pakistan, the indigenous peoples of the Americas and First Nations groups throughout North, Central and South America, indigenous Africans and Asians, as well as Aboriginal Australians, the Papuans of New Guinea and other islands of Melanesia, the Native Hawaiians, and the Māori people of New Zealand. Spanish sociologist Manuel Castells of the University of Southern California Annenberg School for Communication has made extensive use of the term fourth world.
The term originated with a remark by Mbuto Milando, first secretary of the Tanzanian High Commission in Canada, in conversation with George Manuel, Chief of the National Indian Brotherhood of Canada. Milando stated that "When Native peoples come into their own, on the basis of their own cultures and traditions, that will be the Fourth World."
Since publication of Castells' The Fourth World: An Indian Reality (1974), the term Fourth World is synonymous with stateless, poor, and marginal nations. Since 1979, think tanks such as the Center for World Indigenous Studies have used the term in defining the relationships between ancient, tribal, and non-industrial nations and modern industrialised nation-states. With the 2007 UN Declaration on the Rights of Indigenous Peoples, communications and organizing amongst Fourth World peoples have accelerated in the form of international treaties between aboriginal nations for the purposes of trade, travel, and security. In the Indian left movement, Dr. M. P. Parameswaran's ideas on the fourth world caused widespread debates, which eventually led to his expulsion from the Communist Party of India (Marxist) in 2004.
- "International day of the world's indigenous people". Asian Center for the Progress of Peoples.
- Hall, Tony (2003). The American Empire and the Fourth World: The bowl with one spoon. McGill-Queen's native and northern series, 34. Montreal; Ithaca: McGill-Queen's University Press. p. 238. ISBN 0-7735-3006-1. ISBN 9780773530065, ISBN 0773523324, ISBN 9780773523326.
- McFarlane, Peter (1993). Brotherhood to nationhood: George Manuel and the making of the modern Indian movement. Toronto: Between the Lines. p. 160. ISBN 0-921284-67-5. ISBN 9780921284673, ISBN 0921284667, ISBN 9780921284666.
- Griggs, Richard. "The breakdown of states". Center for World Indigenous Studies.
- Ryser, Rudolph C. (September 1993). "Toward the coexistence of nations and states". Center for World Indigenous Studies.
- Cloud, Redwing (10 August 2007). "United League of Indigenous Nations formed". Indian Country Today.
- Castells, Manuel (1998, second edition, 2000). End of Millennium, The Information Age: Economy, Society and Culture Vol. III. Oxford, UK: Blackwell. ISBN 978-0-631-22139-5. Check date values in: