Korean yen
The Korean yen was the currency of Korea between 1910 and 1945. It was equivalent to the Japanese yen and consisted of Japanese currency and banknotes issued specifically for Korea. The yen was subdivided into 100 sen. It replaced the Korean won at par and was replaced by the South Korean won and the North Korean won at par.
Currency swap
South Korea and Indonesia signed a won-rupiah currency swap deal worth US$10 billion in October, 2013. The two nations can exchange up to 10.7 trillion won or 115 trillion rupiah for three years. The three-year currency swap could be renewed if both sides agree at the time of expiration. It is anticipated to promote bilateral trade and strengthen financial cooperation for the economic development of the two countries. The arrangement also ensures the settlement of trade in local currency between the two countries even in times of financial stress to support regional financial stability. As of 2013, South Korea imported goods worth $13.2 billion from Indonesia, while its exports reached $11.6 billion. In August 2018, Qatar and Turkey's central banks signed a currency swap agreement to provide liquidity and support for financial stability.