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.
People's Republic of Korea
When Soviet troops entered Pyongyang on August 24, 1945, they found a local People's Committee established there, led by veteran Christian nationalist Cho Man-sik. Unlike their American counterparts, the Soviet authorities recognized and worked with the People's Committees By some accounts, Cho Man-sik was the Soviet government's first choice to lead North Korea.