Ngāi Tahu, or Kāi Tahu, is the principal Māori iwi (tribe) of the South Island. Its takiwā is the largest in New Zealand, and extends from the White Bluffs / Te Parinui o Whiti, Mount Mahanga and Kahurangi Point in the north to Stewart Island / Rakiura in the south. The takiwā comprises 18 rūnanga corresponding to traditional settlements. According to the 2018 census an estimated 74,082 people affiliated with the Kāi Tahu iwi.

Ngāti Porou is a Māori iwi traditionally located in the East Cape and Gisborne regions of the North Island of New Zealand. Ngāti Porou is affiliated with the 28th Maori Battalion, it also has the second-largest affiliation of any iwi, behind Ngāpuhi with an estimated 92,349 people according to the 2018 census. The traditional rohe or tribal area of Ngāti Porou extends from Pōtikirua and Lottin Point in the north to Te Toka-a-Taiau in the south. The Ngāti Porou iwi also comprises 58 hapū (sub-tribes) and 48 mārae.