History of the League of Nations

Research question: Why and to what extent did League of Nations fail to prevent the WW2 from outbreak, despite its promise for international cooperation, collective security and conflict prevention mechanism?

My decision to examine the history of the League was propelled by my immense interest in the operation of its current successor, United Nations. The League of Nations was the first intergovernmental organization that was established after World War 1 in order to maintain peace. It was headquartered in Geneva, Switzerland and designed to be a forum for handling international disputes before they flared up into military action and caused domino effects that pulled ally nations into the conflict (as had happened with the Great War). Never before had humanity in such extent joined „forces“ in order to prevent states from further aggression, while at the same time preserving the status quo. Unfortunately, the League failed miserably in its intended goal: to prevent another world war from happening (WW2 broke out only two decades later). The idea was for the League to prevent wars from happening through disarmament, collective security, and negotiation. It was also involved in other issues such as drug trafficking, arms trade, and global health. Although the League disbanded during WW2, it was replaced with the United Nations, which is still going strong today, as I mentioned above. From my point of view, one of the main causes and one of my major arguments in the essay of its inability to prevent war was the legitimacy it lacked(US not a member state) to push states for further cooperation and conciliation.

-Start by describing when it was established, by whom, for what reason, what would be the rules, etc.
-Try to constitute what a failure was for LoN, what was actually the aim of the organisation
-Also mention obvious cases when the League of Nations recorded a success as well as failure(Abyssinia crisis, attack of Manchuria by Japan, etc.)

-Please, as one of possible sources, use “Sesan Pedersen: The Guardians”
-please only use peer-reviewed sources, do not use wikipedia at all
Format: Correct formalities (correct citations, within range of 2,000 and 2,500 words, 12pt, double-spaced, etc.)