The indigenous peoples of Oceania are Aboriginal Australians, Papuans, and Austronesians (Melanesians (including Torres Strait Islanders), Micronesians, and Polynesians). These indigenous peoples have a historical continuity with pre-colonial societies that developed on their territories. With the notable exceptions of Australia, New Zealand, Hawaii, New Caledonia, Guam, and Northern Mariana Islands, indigenous peoples make up the majority of the populations of Oceania.
This differs from the term Pacific Islanders, which usually excludes Indigenous Australians, and may be understood to include both indigenous and non-indigenous populations of the Pacific Islands alike.
Australia and most of the islands of the Pacific Ocean were colonized in waves of migrations from Southeast Asia spanning many centuries. European and Japanese colonial expansion brought most of the region under foreign administration, in some cases as settler colonies that displaced or marginalized the original populations. During the 20th century several of these former colonies gained independence and nation-states were formed under local control. However, various peoples have put forward claims for indigenous recognition where their islands are still under external administration; examples include the Chamorros of Guam and the Northern Marianas, and the Marshallese of the Marshall Islands and the Native Hawaiians of Hawaii.
In the pre-Columbian era, humans never reached the handful of oceanic eastern Pacific islands beyond Easter Island, which itself was settled by the Polynesian Rapa Nui people. Eastern Pacific islands such as the Galápagos and Juan Fernández Islands, while inhabitable, did not have a population of Indigenous Americans or Indigenous Oceanians, which helped them form their own unique ecosystems. Author Don Macnaughtan wrote in 2014, "The last places to be reached were in the southwest Pacific, and in the far eastern Pacific. Settlers reached all the way to Easter Island, 2,300 miles from the coast of South America, by about 700AD. In the southwest Pacific, voyaging canoes reached New Zealand around 1250AD, and the remote, cool and windy archipelago of the Chatham Islands around 1300AD (New Zealand was in fact the last major land mass on the planet settled by humans – Iceland was settled about 800AD, and Madagascar some hundreds of years earlier.) After New Zealand, the Pacific was full, and long-range voyaging began to decline quite rapidly. A few habitable Pacific islands were never found until Europeans entered the ocean – they rank as amongst the last places on earth discovered by humans. These include the Galápagos Islands, Cocos Island, the Revillagigedos Archipelago, and the Juan Fernández Islands off the coast of South America; Lord Howe Island in the Tasman Sea between Australia and New Zealand; and Midway Island, northwest of Hawaii. They are some of the few places on the planet which have never had an 'indigenous' population." Lord Howe Island was politically integrated into the Australian state of New South Wales, despite being nearly 800 kilometers removed, and Midway is now an unincorporated territory of the United States. All oceanic islands of the eastern Pacific (excluding Clipperton) were eventually annexed by Central America and South America, after going unclaimed for a few hundred years following their initial discoveries. They are now politically associated with those regions, in addition to sometimes being associated with Oceania. The sparse number of current inhabitants are primarily Spanish-speaking Mestizos. A percentage of Easter Islanders have race-mixed with Mestizo settlers from their current political administrators, Chile, and it has gradually become a bilingual island, where both Spanish and their native language is spoken. Despite this, the inhabitants still view themselves as Polynesians, and by extension Indigenous Oceanians, not South Americans. Linguistics in Oceania (1971) and Island Realm: A Pacific Panorama (1974) both have broad definitions of Oceania, and define eastern Pacific settlers and post-colonial Easter Islanders as making up a Spanish-speaking segment of Oceania.
The Bonin Islands, located about 1,000 to 2,000 kilometers from Tokyo, are commonly thought to have been uninhabited during pre-Columbian times, even though there may have possibly been a Micronesian presence on the islands approximately 2,000 years ago. The islands are still sometimes associated with Oceania, despite now having become politically integrated into Japan. Today, they are sparsely inhabited by Japanese citizens, with a proportion having European and European American ancestry. The European proportion are not recent immigrants, but rather descendants of early settlers, as the islands were not always within the sphere of Japanese colonial influence. Islanders primarily speak Japanese, and like with those in the eastern Pacific, they could be interpreted as one of the smaller linguistic groups in Oceania.
Remoter and more uninhabitable islands adjacent to Micronesia may have had fleeting contact with Indigenous Oceanians, with Howland Island and Wake Island being examples. Norfolk Island (adjacent to Melanesia) and Pitcairn Islands (adjacent to Polynesia) were uninhabited when discovered by Europeans, but there is substantial evidence of prehistoric Indigenous Oceanian settlement. Pitcairn currently have a population of around 50, who are entirely mixed-race Anglo Euronesians. They are descended from an initial group of Anglo and Polynesian settlers in the 18th century. Pitcairn was later annexed by Britain, while Norfolk Island became an external territory of Australia, who are over 1,500 kilometers removed. Norfolk's present population is mostly European Australian, some are also Euronesians; these individuals are descended from Pitcairn Islanders that were relocated to Norfolk in 1852 because of overpopulation. The Micronesia adjacent islands became unincorporated territories of the United States, and they all have no permanent residents. The United States government restrict access to outsiders on some islands.
Oceania is generally considered the least decolonized region in the world. In his 1993 book France and the South Pacific since 1940, Robert Aldrich commented:
With the ending of the Trust Territory of the Pacific Islands, the Northern Mariana Islands became a 'commonwealth' of the United States, and the new republics of the Marshall Islands and the Federated States of Micronesia signed compacts of free association with Washington. Britain's high commissioner in New Zealand continues to administer Pitcairn, and the other former British colonies remain members of the Commonwealth of Nations, recognizing the British Queen as their titular head of state and vesting certain residual powers in the British government or the Queen's representative in the islands. Australia did not cede control of the Torres Strait Islands, inhabited by a Melanesian population, or Lord Howe and Norfolk Island, whose residents are of European ancestry. New Zealand retains indirect rule over Niue and Tokelau and has kept close relations with another former possession, the Cook Islands, through a compact of free association. Chile rules Easter Island (Rapa Nui) and Ecuador rules the Galápagos Islands. The Aboriginals of Australia, the Māoris of New Zealand and the native Polynesians of Hawaii, despite movements demanding more cultural recognition, greater economic and political considerations or even outright sovereignty, have remained minorities in countries where massive waves of migration have completely changed society. In short, Oceania has remained one of the least completely decolonized regions on the globe.— Robert Aldrich (1993), 
In New Zealand, Māori constitute a significant minority, accounting for 16% of the total population according to the 2018 census. A considerable number of those who define themselves as Māori are also of European, and to a lesser but growing extent, of Asian descent.
The indigenous peoples of Australia are the Indigenous Australians, who account for 2.5% of the total population according to 2011 census figures. The term 'Indigenous Australians' refers to both the Aboriginal peoples of mainland Australia and Torres Strait Islander peoples. Of the total 'Indigenous Australian' population, 90% identified as Aboriginal only, 6% identified as Torres Strait Islander and the remaining 4% identified as being of both Aboriginal and Torres Strait Islander origin.
Papua New Guinea (PNG) has a majority population of indigenous societies, with some 700+ different tribal groups recognised out of a total population of just over 5 million. The PNG Constitution and other Acts identify traditional or custom-based practices and land tenure, and explicitly sets out to promote the viability of these traditional societies within the modern state. However, several conflicts and disputes concerning land use and resource rights continue between indigenous groups, the government and corporate entities.
Hawaii boasts a large Micronesian population (including Guamese Chamorros), with many Micronesians having experienced discrimination at the hands of the native Polynesian Hawaiians. Migrants from areas such as the Federated States of Micronesia have also faced discrimination in Guam itself, despite both being ethnoculturally Micronesian.
New Zealand has the largest population of Polynesians in the world; it consists not only of their native Māori population, but also of immigrants from other Polynesian islands, including the Cook Islands, Samoa and Tonga. Australia has the third largest Polynesian population, in addition to having the largest Fijian population outside of Fiji. Australia's Polynesian population consists of Māoris, as well as immigrants who originate from the same countries as the ones who migrated to New Zealand. In 2022, there was controversy over proposals to build a traditional Māori meeting house (known as a Marae) in Sydney. This was seen as disrespectful to Aboriginal Australian landowners, as the Māori are not indigenous to Australia.
The human colonization of remote Oceania occurred in the late Holocene. Prehistoric human explorers missed only the Galápagos and a very few out-of-the-way places as they surged east out of the Solomons, island-hopping thousands of kilometers through the Polynesian heartland to reach Hawaii to the far north, Easter Island over 7500km to the east and, New Zealand to the south
The British added the Ellice, Pitcairn and portions of the Phoenix Islands; the Australians consolidated their claims to Papua; and the French consolidated their claims to Clipperton islands; Easter and adjacent islands were claimed by Chile, Cocos Island was claimed by Costa Rica, and the Galapagos claimed by Ecuador. By 1900 there were virtually no remaining islands in Oceania unclaimed by foreign powers.
Easter Island on the east has been included on the basis of its Polynesian and biogeographic affinities even though it is politically apart. The other islands of the eastern Pacific (Galapagos, Juan Fernandez, etc.) have sometimes been included in Oceania.
Most of this account of the influence of the Hispanic languages in Oceania has dealt with the Western Pacific, but the Eastern Pacific has not been without some share of the presence of the Portuguese and Spanish. The Eastern Pacific does not have the multitude of islands so characteristic of the Western regions of this great ocean, but there are some: Easter Island, 2000 miles off the Chilean coast, where a Polynesian tongue, Rapanui, is still spoken; the Juan Fernandez group, 400 miles west of Valparaiso; the Galapagos archipelago, 650 miles west of Ecuador; Malpelo and Cocos, 300 miles off the Colombian and Costa Rican coasts respectively; and others. Not many of these islands have extensive populations — some have been used effectively as prisons — but the official language on each is Spanish.
[we] can further define the word culture to mean language. Thus we have the French language part of Oceania, the Spanish part and the Japanese part. The Japanese culture groups of Oceania are the Bonin Islands, the Marcus Islands and the Volcano Islands. These three clusters, lying south and south-east of Japan, are inhabited either by Japanese or by people who have now completely fused with the Japanese race. Therefore they will not be taken into account in the proposed comparison of the policies of non - Oceanic cultures towards Oceanic peoples. On the eastern side of the Pacific are a number of Spanish language culture groups of islands. Two of them, the Galapagos and Easter Island, have been dealt with as separate chapters in this volume. Only one of the dozen or so Spanish culture island groups of Oceania has an Oceanic population — the Polynesians of Easter Island. The rest are either uninhabited or have a Spanish - Latin - American population consisting of people who migrated from the mainland. Therefore, the comparisons which follow refer almost exclusively to the English and French language cultures.