The Ngāi Tahu settlement

Ngāi Tahu chiefs signed the Treaty of Waitangi in 1840 at Akaroa, Ruapuke and Ōtākou. Over the next two decades most of the iwi's South Island land passed to the Crown in a series of large purchases; Te Ara counts nine between 1844 and 1863, while the 1998 settlement Act lists ten, from Ōtākou in 1844 to Rakiura in 1864. The largest was the Canterbury purchase of 1848, negotiated by Henry Tacy Kemp, in which 20 million acres were sold for £2,000. NZHistory records that about 37,000 acres were reserved for the tribe's use, leaving Ngāi Tahu with about one-thousandth of their original lands. Ngāi Tahu believed larger reserves should have been surveyed, their food-gathering places set aside, and schools and hospitals located within their villages. In 1879 a Ngāi Tahu leader who had been at the signing of Kemp's deed told a royal commission: 'Kemp promised us reserves, we were to have our fisheries, our burial places, mahinga kai [food-gathering places], eel weirs, anywhere, everywhere. The promises were made 30 years ago! Where is the fulfilment of them?'

The claim, Te Kerēme, was pursued for generations. Matiaha Tiramōrehu made the first formal statement of Ngāi Tahu grievances in 1849, and in the 1870s Hōri Kerei Taiaroa took the claim to Parliament. In Te Ara's account, almost every Ngāi Tahu leader from then until the 1990s was active in the cause. The tribe petitioned Parliament and Queen Victoria and went before the Native Land Court and a series of royal commissions, and inquiries repeatedly described the poverty Ngāi Tahu endured after the sales. A 1920–21 commission suggested compensation of £354,000. The Ngaitahu Claim Settlement Act 1944 instead awarded £300,000, paid at £10,000 a year for 30 years, as a full and final settlement. The Crown later accepted that the 1944 Act was passed without consulting the tribe and did not stop it pursuing its claim.

The 1985 extension of the Waitangi Tribunal's jurisdiction back to 1840 opened the way. On 26 August 1986 Hēnare Rakiihia Tau and the Ngāi Tahu Māori Trust Board, chaired by Tīpene O'Regan, lodged a claim; NZHistory describes it as the first large claim the tribunal heard under its power to investigate grievances dating back to 1840. The tribunal heard it between 1987 and 1989, and its report of 1 February 1991 dealt with the main grievances, known as the 'Nine Tall Trees', and found substantially in Ngāi Tahu's favour. It found that in acquiring some 34.5 million acres for £14,750 the Crown had acted unconscionably and in repeated breach of the treaty, leaving the tribe with too little land to maintain its way of life. Further reports followed in 1992 on the tribe's sea fisheries claim, which was settled through the national fisheries deal, and in 1993 on its smaller claims. In 1996 the Te Rūnanga o Ngāi Tahu Act became, in Te Ara's words, 'the first New Zealand legislation to recognise a tribal group as a political entity'.

With Tīpene O'Regan leading the negotiations for Ngāi Tahu, the deed of settlement was signed on 21 November 1997 by Prime Minister Jim Bolger for the Crown and by Te Rūnanga o Ngāi Tahu; Wikipedia places the signing at Kaikōura, and NZHistory dates the deed to 1998. Its financial value was $170 million, and it gave the tribe the right and opportunity to buy certain Crown assets. Like the Waikato-Tainui settlement, it included a relativity clause. Cultural redress included ownership of pounamu, a role in managing conservation resources, the restoration of some original place names, and rights to sites of significance including Aoraki/Mount Cook. The mountain was to be vested in Te Rūnanga o Ngāi Tahu and then gifted back by the tribe to the people of New Zealand, and Mount Cook National Park was renamed Aoraki/Mount Cook National Park.

The Ngāi Tahu Claims Settlement Act 1998 received assent on 1 October 1998 and was brought into force the same day. In it the Crown acknowledged that it had 'acted unconscionably and in repeated breach of the principles of the Treaty of Waitangi' in its purchases of Ngāi Tahu land, and that its failures had kept the tribe 'for several generations in a state of poverty'. It recognised the 'protracted labours' of Ngāi Tahu ancestors over nearly 150 years and apologised unreservedly for the suffering and hardship caused. In November 1998 Prime Minister Jenny Shipley delivered the apology in person in a speech at Ōnuku marae, near Akaroa on Banks Peninsula. By 2013 almost 55,000 people identified as Ngāi Tahu, then the fourth largest tribe in New Zealand, with the largest territory of any tribe.