Polynesian Triangle in the context of "Enderby Island"

Today the term South Seas, or South Sea, most commonly refers to the portion of the Pacific Ocean south of the equator. The term South Sea may also be used synonymously for Oceania, or even more narrowly for Polynesia or the Polynesian Triangle, an area bounded by the Hawaiian Islands, New Zealand and Easter Island. Pacific Islanders are commonly referred to as South Sea Islanders, particularly in Australia.

The term was coined as Mar de Sur, or "South Sea",  by Spanish conquistador Vasco Núñez de Balboa in 1513 as he it encountered on the southern coast of the Isthmus of Panama and it was applied to the entirety today's Pacific Ocean. In 1520, Ferdinand Magellan named the same ocean the Pacific Ocean, and over time Magellan's name became more well-known.

Polynesia (UK: /ˌpɒlɪˈniːziə/ POL-in-EE-zee-ə, US: /-ˈniːʒə/ -⁠EE-zhə) is a subregion of Oceania, made up of more than 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are called Polynesians. They have many things in common, including linguistic relations, cultural practices, and traditional beliefs.

The term Polynésie was first used in 1756 by the French writer Charles de Brosses, who originally applied it to all the islands of the Pacific. In 1831, Jules Dumont d'Urville proposed a narrower definition during a lecture at the Société de Géographie of Paris. By tradition, the islands located in the southern Pacific have also often been called the South Sea Islands, and their inhabitants have been called South Sea Islanders. The Hawaiian Islands have often been considered to be part of the South Sea Islands because of their relative proximity to the southern Pacific islands, even though they are in fact located in the North Pacific. Another term in use, which avoids this inconsistency, is "the Polynesian Triangle" (from the shape created by the layout of the islands in the Pacific Ocean). This term makes clear that the grouping includes the Hawaiian Islands, which are located at the northern vertex of the referenced "triangle".

Polynesians are an ethnolinguistic group comprising closely related ethnic groups native to Polynesia, which encompasses the islands within the Polynesian Triangle in the Pacific Ocean. They trace their early prehistoric origins to Island Southeast Asia and are part of the larger Austronesian ethnolinguistic group, with an Urheimat in Taiwan. They speak the Polynesian languages, a branch of the Oceanic subfamily within the Austronesian language family. The Indigenous Māori people form the largest Polynesian population, followed by Samoans, Native Hawaiians, Tahitians, Tongans, and Cook Islands Māori.

As of 2012, there were an estimated 2 million ethnic Polynesians (both full and part) worldwide. The vast majority either inhabit independent Polynesian nation-states (Samoa, Niue, Cook Islands, Tonga, and Tuvalu) or form minorities in countries such as Australia, Chile (Easter Island), New Zealand, France (French Polynesia and Wallis and Futuna), and the United States (Hawaii and American Samoa), as well as in the British Overseas Territory of the Pitcairn Islands. New Zealand had the highest population of Polynesians, estimated at 110,000 in the 18th century.

Isla Salas y Gómez (Spanish pronunciation: [ˈisla ˈsalas i ˈɣomes]), also known as Isla Sala y Gómez (Spanish pronunciation: [ˈisla ˈsalaj ˈɣomes]; Rapa Nui: Motu Motiro Hiva), is a small uninhabited Chilean island in the Pacific Ocean. It is sometimes considered the easternmost point in the Polynesian Triangle.

Isla Salas y Gómez and its surrounding waters are a Marine Protected Area called Parque Marino Salas y Gómez, with a surface area of 150,000 km. Throughout its history, the island has been largely untouched by humans, due to its diminutive size and remoteness.

Easter Island (Spanish: Isla de Pascua, [ˈizla ðe ˈpaskwa]; Rapa Nui: Rapa Nui, [ˈɾapa ˈnu.i]) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is renowned for its nearly 1,000 extant monumental statues, called moai, which were created by the early Rapa Nui people. In 1995, UNESCO named Easter Island a World Heritage Site, with much of the island protected within Rapa Nui National Park. Easter Island is also the only territory in Polynesia where Spanish is an official language.

Experts differ on when the island's Polynesian inhabitants first reached the island. While many researchers cited evidence that they arrived around the year 800, a 2007 study provided compelling evidence suggesting their arrival was closer to 1200. The inhabitants created a thriving and industrious culture, as evidenced by the island's numerous enormous stone moai and other artifacts. Land clearing for cultivation and the introduction of the Polynesian rat led to gradual deforestation. By the time of European arrival in 1722, the island's population was estimated to be 2,000 to 3,000. European diseases, Peruvian slave raiding expeditions in the 1860s, and emigration to other islands such as Tahiti further depleted the population, reducing it to a low of 111 native inhabitants in 1877.

Rapa Nui National Park (Spanish: Parque nacional Rapa Nui) is a national park and UNESCO World Heritage Site located on Easter Island, Chile. Rapa Nui is the Polynesian name of Easter Island; its Spanish name is Isla de Pascua. The island is located in the southeastern Pacific Ocean, at the southeastern extremity of the Polynesian Triangle. The island was taken over by Chile in 1888. Its fame and World Heritage status arise from the 887 extant stone statues known by the name "moai", whose creation is attributed to the early Rapa Nui people who inhabited the island starting between 300 and 1200 AD. Much of the island has been declared as Rapa Nui National Park which, on 22 March 1996, UNESCO designated a World Heritage Site under cultural criteria (i), (iii), & (v). Rapa Nui National Park is now under the administrative control of the Ma´u Henua Polynesian Indigenous Community, which is the first autonomous institute on the island. The indigenous Rapa Nui people have regained authority over their ancestral lands and are in charge of the management, preservation and protection of their patrimony. On the first of December 2017, the ex-President Michelle Bachelet returned ancestral lands in the form of the Rapa Nui National Park to the indigenous people. For the first time in history, the revenue generated by the National Park is invested in the island and used to conserve the natural heritage.

Polynesian outliers are a number of culturally Polynesian societies that geographically lie outside the main region of Polynesian influence, known as the Polynesian Triangle; instead, Polynesian outliers are scattered in the two other Pacific subregions, Melanesia and Micronesia. Based on archaeological and linguistic analysis, these islands are considered to have been colonized by seafaring Polynesians, mostly from the area of Tonga, Samoa and Tuvalu.

The closest Polynesian outliers, Anuta and Tikopia in Solomon Islands, were settled some time between the 10th and 13th centuries and subsequently received multiple waves of Polynesian immigration, while the farthest outlier, Nukuoro in the Federated States of Micronesia, was only settled in the 18th century.