1853 American ships reach Tokyo for the first time. It is the end of Japanese isolation from the Western World.
1868 The Japanese Government is overtaken by Samurai who want equality with the West.
1905 Defeated Russia in the Russo-Japanese War. Led to the Japanese wanting more respect and an empire, but they lacked raw materials and food.
1914-18 Fought in WWI with the Allies
1919 Wanted more from the Treaty of Versailles.
1921 Washington Treaty. Japan felt that it was not being treated fairly by the West.
1930 Japan suffered badly in the Depression
1930 Random explosion on the South Manchuria Railway.
Japan blamed sabotage and invaded.
The League told the Japanese to withdraw.
The government agreed but the army did not listen.
What happened next
The Lytton Committee was sent to investigate. It came back saying that there were "faults on both sides".
The League wanted to morally condemn Japan, and the motion was accepted 42:1 (Japan was the one that voted against, but all decisions had to be unanimous)
March 1933 Japan left the League