The independence of New Zealand is a matter of continued academic and social debate. New Zealand has no fixed date of independence; instead, independence came about as a result of New Zealand's evolving constitutional status. New Zealand evolved as one of the British Dominions, colonies within the British Empire which gradually established progressively greater degrees of self-rule. They were always anomalous in international terms, and the attempt to define a "date of independence" in the sense that one can be given for most ex-colonies is not really meaningful. However, a consideration of possible dates can help understanding of the processes of change.