Following World War II, South Korea replaced the yen with an older Korean currency, the won. Each won was divided into 100 jeon (aka chon). However, banknotes were the main form; for South Korean coin collectors, there was only one coin from this period (1945-53) circulated: a 1-jeon coin, issued by the Japanese government.
By the end of the Korean War (1953), the won had devalued to a point where the South Korean government replaced it with a new currency, the hwan. This was theoretically divided into 100 jeon, but no coins or notes were ever circulated for this subdivision.
Three coins were produced for the hwan: 10, 50, and 100. In 1962 the hwan was replaced yet again — with a new won, although 10 and 50 hwan coins were minted until 1975.
See also: South Korea rare stamps for philatelists and other buyers
Following the reintroduction of the won in 1962, the first new won coins were minted in 1966. As with the hwan, modern South Korean won are divided into 100 jeon, but no coins exist for this unit.