It originally operated as a guerilla movement against both the reformist and conservative faction during the late Yi dynasty, and against continued Sierran colonial rule. It developed into a full-fledged political party by the Hanyang Convention in 2nd February 1945, and was decreed by colonial authorities as the sole legitimate ruling party within the archipelago, delcaring the rival Han People's Party as illegitimate. This late fuelled tensions that would culminate in the First Han Civil War.