Hi Graham.
The word is "Maori". The "ao" sounds like the "o" as in "mold" and the "r" is rolled like if you were speaking Spanish the "i" sounds like "e" as in "she". If you are speaking with Maori they really appreciate the pronunciation. Many Kiwis still are lazy about that- saying something like "marry" instead.
I really agree with Stefan on the issue of colonization, introducing a different culture to another is always going to involve troubles, and this is no different in some ways than many other colonial stories. However, Christianity did soften the blow for Maori in many ways often advocating on their behalf with those powers that were bringing in these sweeping changes. Such was the extent of Maoris adopting Christianity that in the early years of colonization there were more Maori Christians than there were European settlers at one point. This can still be observed today by the fact that many Maraes (marae is a fenced-in complex of carved buildings and grounds that belongs to a particular iwi [tribe], hapū [sub tribe] or whānau [family].still have a Christian Church on the grounds.
I'm no expert but I do know that Maoris were having intertribal battles, there were cannibalistic tendencies, there was no comprehension of forgiveness, "utu" meaning revenge was the standard response to injustices. While it is easy to argue that white people brought such things as influenza which at one point decimated the population, they also brought such good things as the rule of law for all, ensuring the principle of equality under the law. Though in practice it didn't happen overnight. New Zealand is struggling right now as a country to come to terms with all of the injustices that the state and private individuals committed against Maori. Such as land confiscation, marginalization, banning the Maori language. Christian missionaries preserved the language by giving them a written language. I'm sorry I don't know more- but am sure there are very good historical accounts of these interactions. I would highly reccommed that you don't just look for histories written by secular authorities, I do know that Christians have also researched and documented histories that will give you more evidence of the Christian influence, particularly the history of preserving their culture in song. The following may give you a lead in your search- good luck.