I don't know about NZ history and NZ segregation specifically but the 1981 Springbok Tour is very relevant on this topic in relation to South Africa. Although Māori have participated in the All Blacks for over a century, tours to apartheid South Africa consciously discriminated and excluded them from playing — even when they were some of the best players of their time, like George Nepia. At one point the NZ Prime Minister cancelled a planned AB tour to SA because of race issues, and I think the SA gov't offered to call the Māori players 'honourary whites' for the next tour. In another AB tour of SA in the 1970s, two dozen African countries boycotted the Montreal Olympics on account of NZ's implicit support of racism and apartheid. This is not even getting into the 1981 tour itself. Keep in mind nationwide riots in NZ happened on the race issue with sports and politics in that time. 48% of NZers were against the tour, 42% were for the tour.
Earlier during the colonization and NZ wars era, there were plans for Māori reservations and electorates after the 1840 Constitution Act. But the reserved land was taken by European settlers and the electorates dropped. The electorates exist today, though.
In general the history education I got in an NZ high school very recently (where all this comes from) highly suggested that the NZ gov't, or at least NZ culture, had whitewashed the idea of Māori-NZer multicultural culture that the Māori began believing in it, and only now have things changed.