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.
Slavery in the 21st century
In North Korea, the government forces many people to work for the state, both inside and outside North Korea itself, sometimes for many years. The 2018 Global Slavery Index estimated that 2.8 million people were slaves in the country. The value of all the labour done by North Koreans for the government is estimated at $975 million USD, with "dulgyeokdae" (youth workers) forced to do dangerous construction work, and "inminban" (women and girl workers) forced to making clothing in sweatshops. The workers are often unpaid. Additionally, North Korea's army of 1.2 million soldiers is often made to work on construction projects unrelated to defense.