This medal is specifically awarded to New Zealanders for service in post-war Japan. It was principally introduced to recognise personnel serving with the British Commonwealth Occupation Force in Japan and so is sometimes referred to as the J Force medal.
This booklet, dating from 1946, is a facsimile of the surrender documents signed on the USS Missouri, in Tokyo Bay, on the 2nd September 1945. These were produced by the National Archives in the US for distribution to institutions and individuals in education. I have the German ones here.
Kiwi Medals 