The League of Nations is almost just a footnote in history. Most notably that it failed in it's stated mission of preventing wars. Any mainstream references usually give the start of WW II as evidence of it's failure. I would argue that the issue is way more complex and nuanced than what the surface details portray.

I would argue that the League of Nations was a first attempt at One World Government pushed by powerful forces within the different countries that existed at the time. Numerous proponents in various mediums of persuasion argued passionately for it to be the vehicle for changing the world. One of those was H. G. Wells as evidenced by a lengthy article published by The Atlantic in 1919. Link provided below.

https://www.theatlantic.com/magazine/archive/1919/01/the-idea-of-a-league-of-nations/306270/

I would argue that one of the main reasons that it failed was due to a correct perception that participating countries would be required to surrender at least some of their sovereignty. At least some of the countries of the time were wary of this and withdrew support and participation from the effort. My understanding is that the U.S. and Russia were two of these countries. It was not too long afterwards that the Bolshevik revolution occurred in Russia and it became a Communist country.

An excerpt from open source info. "The League of Nations was thought up by Woodrow Wilson, the American President during the First World War. ... One of the reasons for its downfall was that, after a vote, the American public refused to join. The League did not have the power it needed to enforce any of the rules that made it up."

You might ask the question of why would I be digging up dead bodies from the past. It is not difficult to see links between The League of Nations and the United Nations organization that we see today. Again a common theme. Give up your sovereignty so that we will have the power to give you peace. Numerous treaties exist between countries and the U.N. that cede control over aspects of the countries governance and it's people. Acquisition of power by stealth. The U.N. has stated that they will have control of the world by 2030. I am praying that they will be disappointed.