From the 1790s, New Zealand was visited by British, French and American whaling, sealing and trading ships. Their crews traded European goods with the indigenous Māori. The first settlers to New Zealand were mainly from Australia, many of them ex-convicts or escaped convicts. Sailors, explorers and traders from Australia and other parts of Europe also settled.
When in 1788 the colony of New South Wales was formed, most of New Zealand was nominally included, but no real legal authority or control was exercised. However, when the New Zealand Company announced in 1839 its plans to establish colonies in New Zealand this and the increased commercial interests of merchants in Sydney and London spurred the British to take stronger action. Captain William Hobson was sent to New Zealand to persuade Māori to cede their sovereignty to the British Crown and on 6 February 1840, Hobson and about forty Māori chiefs signed the Treaty of Waitangi at Waitangi in the Bay of Islands. From this point onward there was considerable European settlement, primarily from England, Wales, Scotland and Ireland; and to a lesser extent the United States, South Africa, and various parts of continental Europe. Some 400,000 settlers came from Britain, of whom 300,000 stayed permanently. Most were young people and 250,000 babies were born. New Zealand ceased to be part of New South Wales and became a British colony on 1 July 1841.
Gold discoveries in Otago (1861) and Westland (1865), caused a worldwide gold rush that more than doubled the population from 71,000 in 1859 to 164,000 in 1863. Between 1864 and 1865, under the New Zealand Settlements Act 1863, 13 ships carrying citizens of England, Ireland and South Africa arrived in New Zealand under the Waikato Immigration Scheme. According to census data from 1871, around half the early settlers were English, a quarter were Irish, a quarter were Scots and 5% were Australian. The European population of New Zealand grew explosively from fewer than 1000 in 1831 to 500,000 by 1881. By 1911 the number of European settlers had reached a million. The settlement of peoples from various foreign countries and the intermingling of the people with the indigenous Māori brought about what would eventually evolve into a "New Zealand accent" and a unique regional English lexicon.
A distinct New Zealand variant of the English language has been recognised since at least 1912, when Frank Arthur Swinnerton described it as a "carefully modulated murmur". From the beginning of the haphazard Australian and European settlements and latter official British migrations, a new dialect began to form by adopting Māori words to describe the different flora and fauna of New Zealand, for which English did not have words of its own.
The New Zealand accent appeared first in towns with mixed populations of immigrants from Australia, England, Ireland, and Scotland. These included the militia towns of the North Island and the gold-mining towns of the South Island. In more homogeneous towns such as those in Otago and Southland, settled mainly by people from Scotland, the New Zealand accent took longer to appear, while the accent was quick to develop in schools starting from the 1890s.
Since the latter 20th century New Zealand society has gradually divested itself of its fundamentally British roots and has adopted influences from all over the world, especially in the early 21st century when New Zealand experienced an increase of non-British immigration which has since brought about a more prominent multi-national society. The Internet, television, movies and popular music have all brought international influences into New Zealand society and the New Zealand lexicon. Americanization of New Zealand society and language has subtly and gradually been taking place since World War II and especially since the 1970s, as has happened also in neighbouring Australia.