What year did New Zealand become a British colony?

New Zealand became a British colony in 1840, following the signing of the Treaty of Waitangi on February 6 of that year. This treaty established the terms under which New Zealand came under British sovereignty and set the foundation for the relationship between the British Crown and the Māori people. The signing of the treaty is recognized as a pivotal moment in New Zealand's history, marking the start of formal British governance in the country.

The other years listed do not pertain to the establishment of British colonial rule. For example, 1769 is significant for the arrival of Captain James Cook, who made the first recorded European contact with New Zealand, but it did not lead to colonization. The years 1907 and 1931 refer to New Zealand's evolution into a dominion and later the Statute of Westminster, respectively, which were important for the country's self-governing status but occurred after the establishment of the British colony in 1840.