Korean currency
In 1902, won was introduced as the official currency unit replacing yang at 1 won = 5 yang. The bank of Korea was established 1909 but soon after in 1910, Imperial Japan annexed Korean Empire. Under Colonial rule, the country was made to use the currency unit "yen" in the name of Korean yen, which took over the Korean won at par. After the division of Korea, the state of South Korea was established and recognized in 1948, and won was again made the official currency of the new state. "jeon" was made the subunit of the currency that divided it into 100 equal parts. Bank of Joseon issued the currency for independent South Korea for the first time that too in banknotes only.
North Korean won
In 2009, another currency reform was initiated to tackle hyperinflation and black market activities. Unlike previous reforms, the 2009 move sparked a nationwide panic when it was announced there would be a two-week waiting period between the withdrawal of the old currency and the introduction of the new currency, coupled with an exchange limit of only 500,000 old won for each person, effectively wiping out savings. The state eventually pulled back on most exchange limits; however, the revaluation proved to be a failure.