An Ariki (Aotearoa or New Zealand, Cook Islands), Ariki (Easter Island), Aliki (Tokelau, Tuvalu), Ali i (Samoa, Hawai i), Ari'i (Society Islands, Tahiti) or Eiki (Tonga) is or was a member of a hereditary chiefly or noble rank in Polynesia.
Aotearoa (New Zealand) Ariki
Political leadership or governance in M ori society has traditionally come from two different groups of people the Ariki and the Rangatira. The Ariki are the "persons of the highest rank and seniority" (p. 58). As the "high-ranking first-born children of first-born children", Ariki inherit their positions from their forebears (p. 142). In particular, their "supreme rank [comes] from the conjunction of a number of senior descent lines from founding ancestors, and ultimately from the gods" (p. 205). Although most Ariki in the past have been male, women, like Te Atairangikaahu, have "brought their own qualities to bear on leadership ... [with] the expectations of them ... [being] the same as for men" (p. 200) .
Ariki do not operate in simple hierarchical orgranisations; despite what "government officers were inclined to believe", Ariki have never been "the apex of a structured hierarchy of institutionalised tribal authority" (p. 264). Many positions overlap with Ariki holding multiple roles, including "head of an iwi, the rangatira of a hapu and the kaumatua of a whanau" (p. 197). Similarly, in times past, "a tohunga may have also been the head of a whanau but quite often was also a rangatira and an ariki" (p. 197). 
Cook Islands Ariki
Arikis at the opening of the 39th Annual General Meeting of the House of Ariki (Cook Islands Herald) Each island in the Cook Islands was ruled by a number of ariki (high chiefs), Rarotonga had about five or six of them, when most of the other islands only had about three - each ariki ruled an ivi or ngati (tribe). Beneath each ariki in the social hierarchy were a number of mataiapo and rangatira (minor chiefs) of noble rank.
Makea Karika Ariki (sitting) and nobles of the Makea Karika tribe, Rarotonga.
A chief's control over his people was related to his mana (power), his mana not only came from birth but also from his achievements and status, this could be gained or lost. An ariki who lost popularity with his people could also be seen as having a decline in mana, which could have led to his loss of control.
Having a control of tapu (sacred matters) was a powerful weapon for the ariki. For supernatural reasons, certain activities were forbidden and since the ariki had control over what was or wasn't forbidden, this gave him considerable power. It was the people's strong belief in an ariki's mana and control over all things tapu that allowed them to take control of their people without the need for physical enforcement.
The ariki, mataiapo and rangatira titles are passed down through the family to the present day, some of the ancient ceremonies and traditions are also still being practiced in the Cook Islands.
The House of Ariki (Are Ariki) is a parliamentary body in the Cook Islands, it was established in 1967 shortly after self-government. It is composed of the Cook Islands high chiefs, it was created to marginalize the ariki giving them dignity but very limited power.
- Ali'i (Hawai'i)
- Makea Takau Ariki (Cook Islands)
- Paramount chief (Oceania)
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