West Irian rupiah

The rupiah was a distinct currency of West Irian (formerly West New Guinea) between 1963 and 1973. It replaced the West New Guinea gulden at par and was replaced by the Indonesian rupiah at the rate of 1 West Irian rupiah = 18.9 Indonesian rupiah.

The presence of the Dutch in Netherlands New Guinea had been a subject of disagreement ever since the treaty that negotiated the Dutch withdrawal from Indonesia in 1949. The Dutch were unwilling to cede to Indonesian control, preferring instead to establish a state of Papua. The Indonesians eventually broke off diplomatic relations with the Dutch, on 17 August 1960. Due to the Indonesians insurgency and confusion over the status of the province, the UN took control as West New Guinea under the authority of the United Nations Temporary Executive Authority on 1 October 1962. On 1 May 1963, UNTEA agreed that the province would be transferred to Indonesia, as Irian Barat (West Irian), a province of Indonesia.

By Presidential decree of Soekarno, on the day of May 1, 1963, the existing Netherlands New Guinean gulden was to be withdrawn, replaced at par, with government-issued coinage, government 1 and 2½ rupiah notes, with larger denomination notes to be issued by Bank Indonesia (the same division between government (aka treasury notes) and bank notes as existed for the Indonesian rupiah). Since the West Irian rupiah was replacing the gulden, which was a much stronger currency than the Indonesian rupiah, the Indonesian currency was not valid tender in Irian, in order to preserve the value of the Irian currency.

Hyperinflation in Indonesia (which due to the separate monetary policy and currency, did not afflict Irian, although inflation was certainly still present) had necessitated a 1000 to 1 devaluation of the national currency in December 1965. It was the intention of the Presidential decree of 13 December 1965 that the 'rupiah baru' (new rupiah) become the unified national currency of all of Indonesia, exchangeable for the Irian Barat rupiah at par. However, a subsequent decree of 15 September 1966 restored the validity of the Irian money, recalling the Indonesian rupiah from Indonesia.

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