The League of Nations was formed after World War I, it was a group that hoped to stop countries in dispute before they would break out into war. It was pretty successful during World War I, but during World War II, so many countries were being taken over by Germany that were apart of the League of Nations, that it crumbled. After the League of Nations became no more, the Allied powers decided to create the United Nations, which was a more powerful and useful version of the League of Nations.