After 1940 , the Japanese encountered tremendous difficulties in administering and garrisoning the seized territories , and tried to solve its occupation problems by implementing a strategy of creating friendly puppet governments favourable to Japanese interests in the territories conquered , most prominently the Nanjing Nationalist Government headed by former KMT premier Wang Jingwei . However , atrocities committed by the Imperial Japanese Army , as well as Japanese refusal to delegate any real power , left the puppets very unpopular and largely ineffective . The only success the Japanese had was to recruit a large Collaborationist Chinese Army to maintain public security in the occupied areas
atrocities
Japanese war crimes
Second Sino-Japanese War