In 2008, the Waitangi Tribunal received a number of requests to inquire into Treaty claims in the Taihape, Rangitīkei, Manawatū, Horowhenua, and Kāpiti areas. Some claims in this region were already in the process of being settled, which included claims associated with Rangitāne ki Manawatū and Ngāti Toa Rangatira. After conferences with the claimants and the Crown, the Tribunal divided the region into two inquiry districts: Taihape and Porirua ki Manawatū.
Approximately 117 claims are being inquired into as part of the Porirua ki Manawatū district inquiry (Wai 2200). The claims of Ngāti Toa, Rangitāne, and Ngāti Apa are not the subject of inquiry, as those claims have been settled. Instead, the inquiry is focused on the claims of Muaūpoko, Te Ātiawa/Ngāti Awa ki Kāpiti and Ngāti Raukawa and affiliated groups, which include Ngāti Kauwhata, Ngāti Wehiwehi and the hapū of Te Reureu.
The western boundary of the Porirua ki Manawatū district extends to the Whangaehu River in the west and down the Kāpiti Coast to near the Porirua Harbour, including Mana and Kāpiti Islands. The southern boundary follows the boundary of the Whanganui-ā-Tara inquiry district from the Tasman Sea to the Tararua Ranges. The eastern boundary aligns with the eastern boundaries of the early Crown purchases and Native Land Court blocks i.e. southward from the eastern boundary of the 1864 Te Āhuatūranga purchase along the Ruahine Ranges, down the eastern boundary of the Manawatū-Kukutauaki blocks in the Tararua Ranges, to the eastern boundary of the Ngārara blocks in the south. The boundary then runs south of Ngārara down the eastern boundaries of the Whareroa and Wainui blocks. The northern boundary follows the northern boundaries of the 1849 Rangitīkei-Turakina purchase, the 1866 Rangitīkei-Manawatū purchase, and the 1864 Te Āhuatūranga purchase, from the Ruahine Ranges to the Whangaehu River.