The back of a 1900 medal commemorating the early part of the South African War. The edge of the medal reads 'Success to New Zealand Contingent 1899-1900'.
The flag depicted is the Flag of the United Tribes of New Zealand, chosen by northern Maori in 1834. (The current New Zealand Flag became our official flag in 1902.)
The front of the medal shows a portrait of Queen Victoria.
The use of the United Tribes flag design on the back of this medal, which was presented to a soldier of the South African War, suggests that before the current flag was instituted, the United Tribes flag may also have been used to represent a distinct New Zealand identity, separate from that of the British Empire and Union Jack.