The League of Nations was an international organisation set up in 1919 to help keep world peace. It was intended that all countries would be members of the League and that if there were disputes between countries they could be settled by negotiation rather than by force. If this failed then countries would stop trading with the aggressive country and if that failed then countries would use their armies to fight.
The first General Assembly of the League of Nations was held on 15 November 1920 with representatives from 41 countries attending.
In theory the League of Nations was a good idea and did have some early successes. But ultimately it was a failure.
Although the idea for the League of Nations had come from Woodrow Wilson, there was a change of government in the United States before the signing of the treaty and the new Republican government refused to join. As a punishment for having started World War One, Germany was not allowed to join and Russia was also excluded due to a growing fear of Communism. Other countries decided not to join and some joined but later left.
The main weapon of the League was to ask member countries to stop trading with an aggressive country. However, this did not work because countries could still trade with non-member countries. When the world was hit by depression in the late 1920s countries were reluctant to lose trading partners to other non-member countries.
When trade embargoes failed to resolve acts of aggression soldiers were to be supplied by member countries. However, countries were reluctant to get involved and risk provoking an aggressive country into taking direct action against them and failed to provide troops.
The Council of the League of Nations only met four times a year and decisions had to be agreed by all nations. When countries called for the League to intervene, the League had to set up an emergency meeting, hold discussions and gain the agreement of all members. This process meant that the League could not act quickly to stop an act of aggression.