The invasion was launched by the bombing of many cities such as Shanghai , Nanjing and Guangzhou . The latest , which began on 22 and 23 September 1937 , called forth widespread protests culminating in a resolution by the Far Eastern Advisory Committee of the League of Nations . The Imperial Japanese Army captured the Chinese capital city of Nanjing , and committed war crimes in the Nanjing massacre . The war tied down large numbers of Chinese soldiers , so Japan set up three different Chinese puppet states to enlist some Chinese support
war crimes
Japanese war crimes
Causes of World War II