After some 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 credibility of the organization was somewhat weakened by the fact that United States never officially joined the League and the Soviet Union joined late and only briefly. Germany withdrew from the League, as did Japan, Italy, Spain, and others. The onset of the Second World War showed that the League had failed its primary purpose, which was to prevent any future world war. The League lasted for 26 years; the United Nations (UN) replaced it after the end of the Second World War and inherited several agencies and organisations founded by the League.
when did the league of nations become the united nations
after the end of the Second World War