Currency of Oceania (Japanese Invasion Money and related material). Geographically, Oceania is a collection of islands scattered throughout the Pacific Ocean comprising Australasia, Melenesia, Micronesia and Polynesia. Numismatically, currency was issued in pound and shilling denominations between 1942 and 1945 by the Japanese as occupation currency on the islands of Kiribati, Nauru, New Guinea, the Solomon Islands, and Tuvalu.