Communist Party of Korea
During the Japanese occupation of Korea, he tried to organize the Korean Communist Party. When the Japanese authorities cracked down on the party, he went into hiding. After Korea's liberation, August 1945, he set up the Communist Party of Korea in the South, but under pressure from American authorities he moved to North Korea in April 1948. He attended a meeting with Kim Gu and Kim Kyu-sik on the subject of Korean reunification.