When did New Zealand gain there independence?

Answer 1

This declaration was adopted at Waitangi on October 28,
1835. Thirty-five ariki and rangatira representing iwi
and hapu from the far north to the Hauraki Gulf signed the
declaration at that hui. Later, other notable leaders added
their signatures; those from outside the Tai Tokerau
included Te Hapuku of Ngati Kahungunu and Potatau Te
Wherowhero of Tainui. The English translation presented
here was sent to the Under Secretary of State at the
Colonial Office in London by James Busby, British Resident
in New Zealand, on 2nd November, 1835.

Answer 2

The British colony of New Zealand became an independent dominion in 1907.

Whether they're fully independent of England may be arguable, but I think they're independent enough to qualify as a sovereign nation.

(See CIA World Factbook below.)

Answer 3

In 1986 the last of Britains powers over New Zealand ended however it was a process over many years. They still have the Britiish Queen as the head of state.

Answer 4

New Zealand was a self-governing Dominion from 1907, and became a self-governing member of the Commonwealth in 1947.

Answer 5

They didn't. They are still technically under British rule. Same with Australia and Canada. The Brits like to take destroy everything they land on. Every recent conflict within the last 100 years is in some way related to them. I am glad the US kicked the crap out of them.