The league of Nations was an intergovernmental organisation founded as a result of the Paris Peace Conference that ended First World War. It was the first international organisation, whose principal mission was to maintain world peace.
After a number of notable successes and some early failures in the 1920s, the League ultimately proved incapable of preventing aggression by the Axis powers in the 1930s. The onset of World War II showed that the League had failed its primary purpose, which was to prevent any future world war. The League lasted 27 years. The United Nations (UN) replaced it after the end of war and inherited a number of agencies and organisations founded by the League.
What is the difference between United Nations and League of Nations?