Causes of Expansion

  • The impact of Japanese nationalism and militarism on foreign policy
  • Japanese Domestic Issues
  • Political Instability in China


  • Japanese invasion of Manchuria and northern China (1931)
  • Sino-Japanese War (1937–1941)
  • The Three Power/Tripartite Pact; the outbreak of war; Pearl Harbor (1941)


  • League of Nations and the Lytton report
  • Political developments within China—the Second United Front
  • International response, including US initiatives and increasing tensions between the US and Japan


  • In 1854, the Kanagawa Treaty was signed, which agreed to open ports for the US.

Causes of nationalism/militarism

  • Victory in the Sino-Japanese and Russo-Japanese Wars
  • Need for resources
  • Need for security
  • Desire to be seen as equal to Europeans
    • Revanchism: aiming to seek revenge for the humiliation of the triple intervention
    • Failure to introduce racial equality in the League of Nations
  • The 1925 Public Security Preservation Law, which was implemented even during the Taisho Democracy period


  • In 1915, Japan presented the 21 Demands to China, which aimed to control Chinese territory and infrastructure. The demands were later decreased to 13 and accepted.
  • The Boxer Rebellion, an anti-colonial movement