In pre - European times the Māori lived off the land. They farmed crops and were a hunter gatherer society. The first European Immigrants arrived as farmers, traders and merchants. Many moved here to escape the feudal authorities where the Lords owned everything in Britain. Land was purchased from the Māori and turned into farmland and towns and cities.
After the civil wars between the Māori and Europeans more land was confiscated. Much of the confiscated land was turned into farmland and leased to European farmers. Many Māori were dispersed from the land and forced to live in the cities and towns. They lost their way of life and were forced to work for the Europeans.
This is how the ruling class and the working class developed in New Zealand. It still exists today. This theory came from Marx.