The present paper,reconstructing the history,in which the theory developed by Louis Boudin,who was an American socialist discussing imperialism from the perspective of historical materialism around the out-break of World War I,was disseminated in Japan and China,asserts that Boudin's theory influenced early Chinese communists such as Li Dazhao and Li Da thanks to Japanese socialists known as Sakai Toshihiko and Hajime Kawakami and finally it sank into oblivion as Lenin's discourses on imperialism prevailed.