The flag of New Zealand, also known as the New Zealand Ensign, is based on the British maritime Blue Ensign – a blue field with the Union Jack in the canton or upper hoist corner – augmented or defaced with four white-bordered red stars, representing the Southern Cross constellation. The current flag was designed and adopted for use on the colony's ships in 1869, was quickly adopted as New Zealand's national flag, and given statutory recognition in 1902.

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