Political map of Australia, New Zealand & the Southwest Pacific 16 November 1840 (Colony of New Zealand): After the signing of the Treaty of Waitangi (1840), the British proclaimed their sovereignty over the main islands of New Zealand, thereby thwarting French (Nanto-Bordelaise Company) and New Zealand Company attempts to establish their own administrations. Initially a dependency of New South Wales, New Zealand was made a separate Crown Colony in November 1840 (Colony of New Zealand).