The United Nations Working Group of Indigenous Populations of the Subcommission on Prevention of Discrimination and Protection of Minorities of the Commission on Human Rights convened for the first time on August 9, 1982.

Subsequently, at the beginning of the International Decade of the World’s Indigenous People in 1994, the General Assembly established the International Day of the World's Indigenous People to be celebrated on August 9 every year during the International Decade of the World’s Indigenous People. In 2004, the Second International Decade of the World's Indigenous People (2005-2014) was declared and continued observance was proclaimed.
In April 2000, the Commission on Human Rights adopted a resolution to establish the UN Permanent Forum on Indigenous Issues that was endorsed by the Economic and Social Council. The mandate of the Permanent Forum is to discuss indigenous issues related to culture, economic and social development, education, the environment, health and human rights.

Who are the Indigenous Peoples?
1972: Working Definition
A definition developed by Mr. José Martinez Cobo, Special Rapporteur on Discrimination against Indigenous Populations, was accepted by the Working Group on Indigenous Populations (Sanders 1989):
"Indigenous populations are composed of the existing descendants of the peoples who inhabited the present territory of a country wholly or partially at the time when persons of a different culture or ethnic origin arrived there from other parts of the world, overcame them, by conquest, settlement or other means, reduced them to a non-dominant or colonial condition; who today live more in conformity with their particular social, economic and cultural customs and traditions than with the institutions of the country of which they now form part, under a state structure which incorporates mainly national, social and cultural characteristics of other segments of the population which are predominant."
Flaws Created:
The definition freezes the identity of indigenous peoples in a historical-chronological axis.
By identifying indigenous peoples with those who 'inhabited' an area before it was conquered or colonized by 'people from other parts of the world,' the definition has limited its applicability mainly to pre-colonial populations. It refers to only 500 years of European colonialism, while it ignores the history of non-European civilizations.
The definition of the indigenous culture, customs, religion, society and history is too simplistic.
The survival of the indigenous identity is explained by its isolation, on the one hand, and its marginalization and discrimination, on the other. It treats the indigenous peoples in terms of an ‘ethnographic present,' as if thousands of years of human history and interactions had never substantially altered the cultures of different peoples.
The definition fails to explain the phenomena of survival of the 'indigenous' identity in the face of adversity.
Ethnic identities have also survived. But not all ethnic communities have lived in isolation. Many ethnic communities have completely lost control over their 'homeland' or the terrain that was the cradle of their culture, yet their identities have survived. What, then, are the differences between the ethnic groups and the indigenous peoples?

1983: A More Inclusive Definition
Realizing that Mr. Cobo's original definition was not adequate to cover the isolated and marginal tribal populations of the Asian continent, the scope and the ambit of the 'working definition' was enlarged. It was decided that all those marginal and isolated groups existing in many countries who may not have suffered conquest or direct colonization might be considered as indigenous peoples if they fulfilled the following criteria:
(a) they are the descendants of groups, which were in the territory at the time when other groups of different cultures or ethnic origin arrived there
(b) precisely because of their isolation from other segments of the country's population they have almost preserved intact the customs and traditions of their ancestors which are similar to those characterized as indigenous
(c) they are, even if only formally, placed under a state structure which incorporates national, social and cultural characteristics alien to their own
(FICN. 41Sub.211983121 Adds. para. 3 79)

1986: Self-identification
The definition was expanded so that any individual who identified himself or herself as indigenous and was accepted by the group or the community as one of its members was to be regarded as an indigenous person (E/CN.4/Sub.2/1986/7/Add.4. para.381). This preserves for these communities the sovereign right and power to decide who belongs to them, without external interference.
The draft Universal Declaration on the Rights of the Indigenous Peoples prepared by the Working Group does not include a definition of indigenous peoples or populations. This omission has been justified by the Chairperson - Rapporteur of the Working Group Ms. Erica Irene Daes on the ground that "historically, indigenous peoples have suffered, from definitions imposed by others" and as a result, in certain countries many indigenous peoples have been declassified.
(E/ CN.4/Stib.2/AC.4/1995/3, page 3).
Excerpt from "Definition and Delimitation of the Indigenous Peoples of Asia", by Tapan Bose.