This year marks the 80th anniversary of the creation of the United Nations Organization. On 26 June 1945, delegations from 50 countries gathered in San Francisco’s Opera House to sign the United Nations Charter, a document laying out the structures and functions of a new world security organisation. After years of war, a global conflict that saw an unprecedented scale of violence and destruction, world leaders aimed to design an institution that could help maintain peace and security in the decades ahead. According to the new charter, countries would now be bound by international law, they would work through peaceful means to achieve political ends, and they would use collective force to punish and deter aggressors.

In what was a great irony, the organisation never worked exactly as it was intended. Deep rooted differences between the Soviet Union and Western powers meant that their future cooperation – what was a key assumption behind the new organisation – was jeopardised from the start. Nonetheless, the United Nations lived on, becoming the greatest international organisation the world has ever known. Many historians have charted its successes and failures between January 1946, when the first meeting of the General Assembly took place, and the present day; but less attention has been given to its wartime origins, and how exactly leading statesmen and officials conceived of and planned for the world to come.

The history of the creation of the United Nations cannot be told without reference to its immediate predecessor, the League of Nations. Designed in the final years of the First World War and agreed to at the Paris Peace Conference of 1919, the League represented the first truly international organisation dedicated to the maintenance of peace and security throughout the world. Its most prominent advocate, the American President Woodrow Wilson, viewed the League as ushering in a new form of diplomacy – a way to fundamentally change the nature of international politics. Violent conflict had long characterised the relations between nation-states, but this new organisation was to provide a new code of conduct and a forum for settling disputes between governments. Countries would no longer be allowed to resort to war to achieve their intended aims, and those violating the Covenant of the League of Nations would be punished by the collective action of its members. While the 1920s saw some successes for the nascent organisation, the following decade would see it sidelined and ultimately ignored. The revisionist aims of powers like Japan, Germany and Italy – and more specifically the violent methods by which these countries sought to achieve their objectives – were met with indecision and inaction from the League’s most powerful members. By the end of the decade and with the start of the Second World War, many considered the League of Nations a failed internationalist experiment.

Yet in the early years of the Second World War, many citizens along with their leaders, still believed an international organisation, if it could be properly designed and backed with adequate force, would help prevent violence and destruction for future generations. A common argument was that it was not the League that failed as much as its members who, when confronted with great challenges, refused to take concerted action. In the first years of the war, many writers, activists, and eventually government officials within allied nations began to outline plans for a new world organisation, one that could be more powerful and more effective than the post-1919 precedent.

The first great development on the road to the United Nations Organization was the signing of the Atlantic Charter between American President Franklin Roosevelt and British Prime Minister Winston Churchill. Across eight points, the two leaders laid out general principles which inspired an anti-Axis coalition and would go on to shape the post-war world. Included in this joint declaration – point 8 to be exact – was mention of the need for nations to abandon the use of force and to create a “wider and permanent system of general security.” Months later, in late December 1941, Roosevelt and Churchill drew up another declaration which was signed by dozens of allied nations at the beginning of the New Year. This ‘United Nations Declaration’, as it was known, became the moment when governments agreed to join together to fight against the Axis powers in the war and then to lay the foundations of a new international system.

Between 1942 and 1943, numerous individuals, interest groups and world leaders spoke of the need to establish a new and peaceful world order. But it was in the capitals of the United States, Britain, the Soviet Union, and China where officials were working to draft concrete plans for what such a system might look like. Each described a future organisation that looked somewhat like the League of Nations. They recommended the creation of an assembly where all nations could gather together and address pressing challenges, and they also called for some council of great powers (each government included the United States, Britain, the Soviet Union and China in this council) that would be primarily responsible for the maintenance of peace and security. Planners looked to the precedent of the League of Nations and judged that what had weakened the previous organisation was the inability to decide on and deploy military force to resist aggression. They believed that a smaller grouping of powers working closely in concert could provide for the deterrent force which the League had lacked.

At the Dumbarton Oaks Conference which met in Washington, D.C., between August and October 1944, the British, Americans and Soviets agreed on the basic outlines of a new world organisation (the Chinese were at first excluded from these meetings with the Soviets at the insistence of leaders in Moscow, who feared it would jeopardise their non-aggression treaty with Japan). The three powers, as well as China who signed on to the proposals once they were able to meet with the American and British delegations, agreed to establish a Security Council, a General Assembly, a Secretariat, and an International Court. It was to be a hierarchical organisation, one where the great powers held ultimate authority for when to use force against countries violating the organisation’s charter. And at the root of this blueprint for a future international security organisation was an assumption that would eventually prove hollow – namely, that the great wartime allies would remain united in the peace.

Despite their agreement at the Dumbarton Oaks Conference, there were several outstanding issues which had yet to be solved. The Americans and the British favoured the permanent members of the Security Council (the United States, Britain, the Soviet Union, China, and eventually France) not being able to veto decisions concerning disputes in which they themselves were involved; whereas the Soviet Union insisted that the great powers should retain the veto at all times. A second issue was the Soviet request to have all of its 16 constituent republics brought into the organisation as individual members – a suggestion which the Americans and British feared would give it a disproportionate voting influence in the wider organisation. These differences would not be settled until the Yalta Conference in February 1945.

Into late 1944, a host of governments and countless organisations and individuals weighed in on what had been agreed between the great powers at Dumbarton Oaks. A major criticism was the authority placed in the hands of the permanent members of the council. The ability to veto any decision taken by the Security Council (and initially the ability to veto any discussion from taking place in the Security Council) was a major source of contention. The pushback led to certain measures being taken by the great powers, and specifically the British, to find a solution to the question of the veto. Another issue which came up in these months – and one that would go on to shape the ultimate nature of the organisation – was the question of regional organisations that might sit under the world organisation. A number of countries, from France to Australia and Mexico, were adamant that individual nations be allowed to develop regional alliances, and for these alliances to be able to take action without approval of the United Nations Security Council. These efforts had a great impact on the ultimate shape of the United Nations Charter, specifically Article 51, which allowed for regional organisations to act in self-defence without prior authorisation from the council. Though a seemingly trivial detail, this stipulation had a profound effect on the nature and functioning of the world organisation.

By the time Roosevelt, Churchill and Stalin came together at the Yalta Conference in February 1945, there was great concern that the remaining differences between these three governments would prevent the creation of the United Nations Organization. After tense negotiation, the Soviets eventually acquiesced to a compromise which had been first proposed by the British and later adopted by the Roosevelt administration. Under this formula, the permanent members of the Security Council would be able to veto any decision taken by the council, but they would not be able to prevent disputes from being discussed in the international organisation. This compromise is what ultimately saved the United Nations during its wartime formation.

Though Yalta represented a great achievement for these governments when it came to the post-war organisation, the optimism which marked the end of the meetings soon soured, as Anglo-Soviet relations descended into mutual suspicion. Soviet moves in Romania and Poland, along with disputes about invitations to the San Francisco Conference, led to Stalin’s initial refusal to send his Foreign Minister to California. This move, coupled with a wrinkle in Anglo-American relations over the subject of colonial trusteeship, led the British and Americans to consider a postponement of the conference in March.

The San Francisco Conference eventually convened in late April and ran through the end of June. Here 200 delegates from dozens of countries gathered to debate the Dumbarton Oaks proposals initially agreed by the four great powers. Many of the negotiations were contentious, as smaller and medium powers tried to wrestle influence away from the Security Council and towards the General Assembly. Though certain concessions were made by the American, British, and Soviet delegations, the United Nations Charter closely resembled the earlier Dumbarton Oaks Proposals – blueprints which had placed unprecedented responsibility in the hands of its most powerful members. The Charter’s 111 articles set out the basis for a world security organisation that was intended to maintain peace and foster prosperity throughout the world. As representatives from 50 countries signed the charter on the 26th of June (a 51st member, Poland, eventually signed in October), there was great optimism that the organisation would usher in a new era of world politics.

These high hopes soon subsided as intractable differences between the Western powers and the Soviet Union led to an emerging global struggle. What would become known as the Cold War defined, to a large degree, international politics for the next four decades. Though the core members of the Security Council were rarely on the same side of an international dispute – a fact that hindered the council from functioning as originally intended – the United Nations lived on. Its charter continued to provide a benchmark of international rules and norms; it served as a forum for nations large and small to raise concerns; it played a key role in helping newly independent nations to take their place in an international system; it has served as an effective peacekeeping mechanism in various regions of the world; and it has facilitated international cooperation across a range of common challenges. As of 2025, there is great debate over its future purpose in a changing global landscape, but one thing remains certain: the United Nations Organization, with its 190-plus members, has been and will remain the greatest internationalist institution in human history.

Where to Find Documents within the Churchill Archive

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