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The League of Nations

After World War I, US President Woodrow Wilson helped to build an international peacekeeping organization.  


  • The League of Nations was established at the end of World War I as an international peacekeeping organization.
  • Although US President Woodrow Wilson was an enthusiastic proponent of the League, the United States did not officially join the League of Nations due to opposition from isolationists in Congress.
  • The League of Nations effectively resolved some international conflicts but failed to prevent the outbreak of the Second World War.

The experience of the First World War

World War I was the most destructive conflict in human history, fought in brutal trench warfare conditions and claiming millions of casualties on all sides. The industrial and technological sophistication of weapons created a deadly efficiency of mass slaughter. The nature of the war was thus one of attrition, with each side attempting to wear the other down through a prolonged series of small-scale attacks that frequently resulted in stalemate.
Though the origins of the war were incredibly complex, and scholars still debate which factors were most influential in provoking the conflict, the structure of the European alliance system played a significant role.1 This system had effectively divided Europe into two camps, based on treaties that obligated countries to go to war on behalf of their allies.
In the immediate aftermath of the war, American and European leaders gathered in Paris to debate and implement far-reaching changes to the pattern of international relations.2 The League of Nations was seen as the epitome of a new world order based on mutual cooperation and the peaceful resolution of international conflicts.

The establishment of the League of Nations

The Treaty of Versailles was negotiated at the Paris Peace Conference of 1919, and included a covenant establishing the League of Nations, which convened its first council meeting on January 16, 1920.
The Council of Four at the Paris Peace Conference, including British Prime Minister David Lloyd George, Italian Premier Vittorio Orlando, French Premier Georges Clemenceau, and US President Woodrow Wilson. Image courtesy Wikimedia Commons.
The League was composed of a General Assembly, which included delegations from all member states, a permanent secretariat that oversaw administrative functions, and an Executive Council, the membership of which was restricted to the great powers.3 The Council consisted of four permanent members (Great Britain, France, Japan, and Italy) and four non-permanent members. At its largest, the League of Nations was comprised of 58 member-states. The Soviet Union joined in 1934 but was expelled in 1939 for invading Finland.
Members of the League of Nations were required to respect the territorial integrity and sovereignty of all other nation-states and to disavow the use or threat of military force as a means of resolving international conflicts. The League sought to peacefully resolve territorial disputes between members and was in some cases highly effective. For instance, in 1926 the League negotiated a peaceful outcome to the conflict between Iraq and Turkey over the province of Mosul, and in the early 1930s successfully mediated a resolution to the border dispute between Colombia and Peru.
However, the League ultimately failed to prevent the outbreak of the Second World War, and has therefore been viewed by historians as a largely weak, ineffective, and essentially powerless organization.4 Not only did the League lack effective enforcement mechanisms, but many countries refused to join and were therefore not bound to respect the rules and obligations of membership.

The United States and the League of Nations

US President Woodrow Wilson enunciated the Fourteen Points in January 1918. The Fourteen Points laid out a comprehensive vision for the transformation of world politics. Wilson believed that affairs between nations should be conducted in the open, on the basis of sovereignty, self-determination (the idea that all nations have the right to choose their own political identity without external interference), and the disavowal of military force to settle disputes. Wilson’s vision for the postwar world was hugely influential in the founding of the League of Nations.5
The British magazine Punch satirized Wilson's grand dreams of world peace through the League of Nations. In this cartoon, Wilson holds out a very large olive branch marked 'League of Nations' to a dove that is too small to grasp it. Punch March 26, 1919. Image courtesy Wikimedia Commons.
President Wilson’s intense lobbying efforts on behalf of US membership in the League of Nations met with firm opposition from isolationist members of Congress, particularly Republican Senators William Borah and Henry Cabot Lodge. They objected most vociferously to Article X of the League’s Covenant, which required all members of the League to assist any member threatened by external aggression. In effect, Article X would commit the United States to defending any member of the League in the event of an attack. Isolationists in Congress were opposed to any further US involvement in international conflicts and viewed Article X as a direct violation of US sovereignty. As a result, the Senate refused to ratify the treaty, and the United States never became a member of the League of Nations.6
Though the League had failed to prevent the outbreak of another world war, it continued to operate until 1946, when it was formally liquidated. By this time, the Allied powers had already begun to discuss the creation of a new successor organization, the United Nations. The United Nations, which is still in existence today, was based on many of the same principles as the League of Nations, but was designed specifically to avoid the League’s major weaknesses. The UN boasts much stronger enforcement mechanisms, including its own peacekeeping forces, and the membership of the UN is substantially larger than that of the League even at its peak.

What do you think?

Why did the United States refuse to join the League of Nations?
How effective was the League of Nations as an international peacekeeping organization?
Do you think the League of Nations could have prevented the outbreak of the Second World War if the United States had joined?

Want to join the conversation?

  • winston default style avatar for user Sooroome Sami
    Why did they create the cartoon of Woodrow giving the dove bird the oversize branch marked the League of Nations?Isn't that the biggest insult to Woodrow and the League of Nations?
    (14 votes)
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    • blobby green style avatar for user Posts Only
      You could view it that way but I think the implied criticism is not against Wilson as much as it is a sarcastic jab at the world's general lack of will and commitment to peace. The age of imperialism was not yet over and war or the threat of war were still viewed as useful if not indispensable tools of nation's expansionist goals.
      (43 votes)
  • blobby green style avatar for user martinez.miguel8909
    Why did the Wilson not help even though it was his idea?
    (7 votes)
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  • leaf red style avatar for user Carla Cristina Almeida
    "The United Nations, which is still in existence today, was based on many of the same principles as the League of Nations, but was designed specifically to avoid the League’s major weaknesses." what exactly were these weaknesses?
    (6 votes)
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    • blobby green style avatar for user Muhammad Haad Khan
      Actually the weaknesses of the League were more deep-seated ones. Like a major drawback for the League was that it lacked a basic collective security force or you can say it does not have its own army and had to rely upon member states to provide it with support. Another one is that the members openly defied the League, for example Russia's invasion of Finland, and the League was unable to take drastic steps to pin down any such aggression. Additionally, its a bit weird to say this way but the members didn't took the League 'seriously' because there was open defiance, reluctance to abide by the League's rulings,inability to control the open embark of Germany on a military expansion program under Hitler, inability to stop Japan from invading China etc. So basically as said by Pedersen above: UN just tried to patch up the holes. See if that helps? :)
      (19 votes)
  • piceratops seed style avatar for user Rose Smith
    What were some of the requirements and restrictions for the nations that belonged to the League of Nations?
    (6 votes)
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    • female robot grace style avatar for user Alpha Juliet
      For starters, all member-states had to respect the territory of all other nations, meaning they couldn't just annex other countries' territory. Every member-state also had to respect other nations' sovereignty (their authority to be self-governing), which effectively banned the creation of empires.

      Another requirement of member-states – one that the US Congress disagreed with so strongly that they never joined – was that if a member-state was attacked by an outside force, all other members had to support the attacked nation, essentially drawing the entire League into the conflict.

      This is definitely not an exhaustive list, but it includes some of the major regulations. Hope this helps!
      (14 votes)
  • blobby green style avatar for user kkacharava.newschool
    To what extent was the League of Nations doomed to fail due to the limitations of its covenant and structure?
    (5 votes)
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    • mr pants purple style avatar for user Zoilo McCrocklin
      The League of Nations was not an entire failure and had great intentions; however, the limitations of the LoN (no control over non-members, lack of security force and inability to control actions of members or prevent actions of members) led to countries being able to take advantage of these weaknesses and eventually led to the end of the League of Nations and an improved United Nations! So, all in all, the League of Nations was not a failure because it led to peace in some instances and paved the way for the UN. However, its limitations was enough to keep it from being effective as a permanent organization.
      (1 vote)
  • mr pants purple style avatar for user Lilleanna McCoy
    When considering the outcome of WWI and the failure of the League of Nations, what lessons did the United States learned over time about being heavily involved in global affairs?
    (3 votes)
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    • stelly blue style avatar for user SweetSourBlueberry
      Great Question!

      The United States failed to support the League of Nations. There are a few reasons for this. The League of Nations was part of the Versailles Treaty ending World War I. It was supposed to be an organization where countries could bring their problems to discuss and hopefully work out a peaceful settlement instead of fighting over them.
      (3 votes)
  • blobby green style avatar for user ijafiya.ijanada
    What ways has international organizations contributed to peace keeping and stability I world politics.
    (3 votes)
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  • starky seed style avatar for user tasnim babar
    What was France's stance regarding the proposal of the formation of the League of Nations? As in, did they agree or disagree with this, and why?
    (2 votes)
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  • stelly orange style avatar for user smorillo0303
    which countries were not allowed in the league of nations?
    (2 votes)
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  • blobby green style avatar for user dpatel2231
    what were the two mistakes made by president wilson?
    (3 votes)
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    • starky sapling style avatar for user Joshua
      From what I remember, and correct me if I'm wrong.
      He liked negotiating about the points (I think) and it was kinda pushing the League back

      Sorry if this wasn't helpful....please correct me if I'm wrong!
      (1 vote)