North Korea
Japan tried to suppress Korean traditions and culture and ran the economy primarily for its own benefit. Korean resistance groups known as Dongnipgun (Liberation Army) operated along the Sino-Korean border, fighting guerrilla warfare against Japanese forces. Some of them took part in allied action in China and parts of South East Asia. One of the guerrilla leaders was the communist Kim Il-sung, who later became the first leader of North Korea.
Workers' Party of North Korea
When the Supreme People's Assembly met in early September 1948, 102 out of 212 delegates came from the Workers Party. The Supreme People's Assembly declared the foundation of the Democratic People's Republic of Korea, with Workers Party Vice-Chairman Kim Il-sung as its prime minister.