During the Second World War, an unlikely alliance was formed in order to defeat Nazi Germany. This alliance reunited diverging ideologies but was necessary to ensure victory.
The three great allied powers, Great Britain, the United States, and the Soviet Union (USSR), formed a Grand Alliance in order to defeat the Axis powers of Nazi Germany, Fascist Italy, and Japan. This alliance was led by Winston Churchill (Britain), Franklin Roosevelt (US), and Joseph Stalin (USSR), the so-called ‘Big Three’.
A series of conferences between the Allied leaders and their military officials allowed them to gradually decide the direction of the war, the members of the alliance, and eventually the post-war international order.
The Grand Alliance or the ‘Strange Alliance’
The Alliance partners did not share common political aims and did not always agree on how the war should be fought. Although the United Kingdom and the United States maintained close relations thanks to their bilateral Atlantic Charter, they were capitalist countries, while the USSR had been communist since the 1917 Russian Revolution. Nazi aggression against the USSR in 1941, through Operation Barbarossa, turned the Soviet regime into an ally of Western democracies.
The Grand Alliance brought together two sides divided by their political and economic ideologies. In the post-war world, these increasingly divergent viewpoints created tension between those who had once been allies and signalled the beginning of the Cold War.
How was the Grand Alliance formed in 1941?
The Grand Alliance was formed and consolidated thanks to numerous conferences and agreements. The main ones are described below:
The Atlantic Charter
In August 1941, the Axis powers were winning the war, both in Europe and Asia. The United States had not yet entered the war and provided only moral and material support to the Allies.
However, on 14 August, British Prime Minister Winston Churchill and US President Franklin Roosevelt issued a joint declaration known as the Atlantic Charter. This was not a treaty between the two powers but simply set out their vision for the post-war world. Their joint declaration included promoting democracy and free trade, as well as increasing opportunity for all.
The principles of the Atlantic Charter received support when representatives from ten governments met in London shortly after the announcement of the charter. This declaration was signed on 24 September by nine exiled governments of occupied Europe as well as the USSR.
Fig. 1 - President Franklin D. Roosevelt (front left) and Prime Minister Winston Churchill (front right) on the HMS Prince of Wales for Sunday Service during the Atlantic Conference, 10 August 1941
The United Nations Declaration
The United Nations Declaration was a short document signed by the Allied ‘Big Three’ and China on New Year’s Day 1942, during the Arcadia Conference. The next day, the representatives of 22 other nations added their signatures. These governments pledged to accept the Atlantic Charter and would not negotiate a separate peace deal with any of the Axis powers.
The other signatories were the four dominions of the British Commonwealth, eight exiled European governments, nine countries in South America, and the British-appointed Government of India.
Then, between 1942 and 1945, the principal treaty that formalised the Allies of the Second World War was signed by 47 governments: this was the Declaration by United Nations. This declaration also became the basis of the United Nations, ratified by the UN Charter and signed by 50 countries on 26 June 1945.
The Moscow Declaration
The Moscow Declarations were four declarations signed during the Moscow Conference on 30 October 1943. Representatives from Great Britain, the United States, China, and the Soviet Union signed the Moscow Declarations which were as follows: the Declaration of the Four Nations on General Security, the Declaration on Italy, the Declaration on Austria, and the Declaration on Atrocities.
The Moscow Conference indicated that the principal Allied nations were working together to achieve victory and create a world in which ‘men in all lands may live out their lives in freedom from fear and want.’
The Grand Alliance in the Tehran Conference
The Tehran Conference, codenamed Eureka, was the first time the ‘Big Three’ met in person. Joseph Stalin, Franklin D. Roosevelt, and Winston Churchill held a strategy meeting between 28 November and 1 December 1943, in Tehran, the capital of Iran.
The conference’s main outcome was to work out the roadmap for the Allies' final strategy to win the war. This is where the Western Allies, the United States, and Great Britain agreed to open a second front against Germany, to alleviate the pressure the Red Army was facing on the Eastern Front. At this time, the Soviet Union was facing the majority of the Nazi military resources.
Consequences of the Grand Alliance: the four policemen
The ‘Four Policemen’ was a term coined by Roosevelt as he referred to the four major Allied powers of the Second World War: the ‘Big Three’ and China. This phrase symbolised the US President’s conception of the post-Second World War world.
Roosevelt believed that each of the four policemen would maintain order in their respective spheres of influence: Britain in Western Europe and its empire, the USSR in Eastern Europe and Central Asia, China in East Asia and the Western Pacific, and finally the US in the whole Western Hemisphere.
Roosevelt anticipated that the United States would dominate China’s sphere given the weakness of Chiang Kai-shek’s government. This would mean that the US would have control over two spheres and be able to maintain its supremacy over the world, whilst Britain declined and the Soviet Union reeled from its losses after the war.
What did the ‘Big Three’ disagree on?
There were a number of key tensions between the leaders. The main ones were the course of the war, post-war Germany, Poland, and Eastern Europe. These are best understood by examining the debates at each of the wartime conferences and the secret agreements that some of the allies made.
Debates at the Tehran Conference
These were some of the main points discussed during the Conference:
At the Tehran Conference, Stalin demanded the creation of a second front in Western Europe in order to relieve the pressure on the Soviet Union. Churchill favoured opening a second front in the Balkans, but Roosevelt sided with Stalin to support a second front in Western Europe. Although this was agreed, the delay in opening this front until June 1944 was a cause of tension.
The US and UK wanted the Soviet Union to open a second front in Asia against Japan, but Stalin refused until Germany was defeated.
Stalin wanted to take reparations from Germany, whilst Churchill and Roosevelt wanted to rebuild the country in order to avoid similar consequences to those of The Treaty of Versailles, which contributed to the start of the Second World War. The three powers were only able to agree that Germany’s unconditional surrender was the goal.
Stalin demanded territory from Poland and a pro-Soviet government in the country. The US and the UK reluctantly agreed to it and would compensate Poland with land from Germany.
Stalin demanded the right to keep the Baltic States, Finland, and Romania. The Soviet desire for a sphere of influence in Eastern Europe would become a major issue.
It was agreed that British and Soviet troops stationed in Iran would withdraw after the war ended.
The Percentages Agreement
On 9 October 1944, Churchill and Stalin secretly made a ‘percentages agreement’, dividing the states of eastern and southern Europe between them. Churchill acted without the US as they were critical of British imperialism, and Churchill wanted to protect British interests.
The Polish question
The question of a new government for Poland became a key point of conflict between the powers. There were two groups of Poles with opposing political views: the London Poles and the Lublin Poles.
The London Poles had fled to London after France fell to the Nazis in 1940. They were opposed to Soviet policies and demanded a free government as compensation for land sacrifices.
The Lublin Poles were pro-Soviet and wished to work with the Soviet Union. As such, the Soviet Union recognised them as the only lawful authority in Poland when they formed the ‘Committee of National Liberation’ in July 1944. This group of Poles became the provisional government of Poland in December of that same year.
Debates at the Yalta Conference
In February 1945, the three leaders met again. By this point, Stalin’s Red Army occupied most of Eastern Europe and started to support communist groups.
Stalin agreed to enter the war in exchange for territory.
It was agreed that Germany would be divided into four zones, and would pay $ 20 billion in reparations, 50% of which would go to the USSR.
Poland’s borders were decided, and Stalin agreed to conduct free elections.
Stalin also agreed to free elections in Eastern Europe.
Debates at the Potsdam Conference
In July 1945, after the surrender of Nazi Germany in May, Stalin met once more with the US and UK leaders. However, Roosevelt had been replaced by the more hard-line Harry Truman, and halfway through the conference, Clement Atlee replaced Churchill as UK Prime Minister.
They agreed that each of the four zones would be dealt with in its own way but the economy would run as a whole. The Soviet Union could take whatever they wanted from their zone but 10% from the Western zone.
Truman was unhappy with the configuration of the Polish government and demanded the inclusion of more London Poles, and free elections.
Truman disapproved of the Percentages Agreement, fearing that Eastern Europe would become a Soviet sphere of influence.
On 16 July 1945, the day before the conference, the US successfully tested the first atomic bomb without telling the Soviet Union. The US planned to use their new weapons against Japan and did so in August 1945, ending the war.
Why did the Grand Alliance break down?
The tensions were not enough to break the Alliance during wartime, but relations had significantly worsened by the end of the war and the lack of a mutual enemy caused issues to escalate.
The countries feared the motivations and aims of the other nations, which led to distrust between them. In fact, Stalin was extremely suspicious, to the point of paranoia, of Roosevelt and Churchill. He was worried they would oppose his expansion of Soviet influence in Eastern Europe as soon as the war ended.
At the same time, the USA emerged more powerful from the war than the Soviet Union and expressed its concern about the spread of communism. This would lead to the breakdown of the alliance and eventually to hostility. Truman regarded the dominion of Soviet influence on Eastern Europe as an act of aggression.
The following events led to the final breakdown of the Grand Alliance:
Stalin did not conduct the free elections in Poland and Eastern Europe that he promised. The Polish ‘free’ elections of January 1947 were not in fact free. The opposition candidates were disqualified, arrested, and even murdered in order to ensure a communist victory.
Communist governments were also secured throughout Eastern Europe. By 1946, Moscow-trained communist leaders returned to Eastern Europe in order to ensure these governments were dominated by Moscow.
Against the agreement made at Tehran that the Soviet Union would withdraw its troops after the end of the war, 30,000 Soviet troops remained in Iran. Stalin refused to remove them until in March 1946, Iran referred the situation to the United Nations.
After the Second World War, Greece and Turkey were highly unstable and involved in nationalist and pro-communist rebellions. This was not in line with the Percentages Agreement which angered Churchill, as Greece and Turkey were supposedly in the Western ‘sphere of influence.’
The communist parties in Italy and France became stronger after the war due to economic difficulties in those countries. The US and the UK were alarmed and believed that Moscow was playing a part.
In February 1946, George Kennan’s famous telegram explained Soviet foreign policy to the US state department. He said that the Soviet Union was hostile to the West and only listened to the ‘logic of force.’ This went on to shape the US policy of containment.
On 5 March 1946, Churchill gave a speech in Missouri warning of an iron curtain descending across Europe ‘from Stettin in the Baltic to Trieste in the Adriatic’ with the Soviet Union’s takeover of Eastern Europe. This expressed Churchill's view of the Soviets, who were not respecting the Yalta conference.
In response, Stalin compared Churchill to Hitler, withdrew from the International Monetary Fund (IMF), and increased anti-Western propaganda.
By 1947, cooperation between the Western Allies and the Soviets had completely broken down. The world became deeply divided between the Western powers who promoted capitalism and the Soviet Union which embraced communism: the Cold War had started. The period 1945–49 is considered the origins of the Cold War.
The Grand Alliance - Key takeaways
The Grand Alliance was an alliance led by the ‘Big Three’, the three great Allied powers: Great Britain, the United States, and the Soviet Union, in order to defeat Nazi Germany and its allies, during the Second World War. This alliance was created out of necessity, and brought together two sides divided by their political and economic ideologies. They did not always agree on how the war should be fought and had differing political aims.
The Grand Alliance was formed and consolidated thanks to numerous conferences and agreements, most notably the Atlantic Charter which established the common aims of the UK and US, the United Nations Declaration which formalised the Alliance, and finally the Moscow Declarations which set out the post-war vision of the Alliance.
The Tehran Conference was the first time the ‘Big Three’' actually met in person. During this meeting, the main military operations to end the war were agreed: the US and UK would launch the Normandy beach landings whilst the USSR initiated another major offensive along the Eastern Front.
- Stalin’s main post-war objective was to have a loyal sphere of influence, which led him to violate agreements of free elections in Poland and Eastern Europe made during the wartime conferences.
The Grand Alliance finally broke down as the Second World War ended, and tensions concerning the post-war world arose. By 1947, the confrontation between the ex-allies had started, and this signalled the beginning of the Cold War.
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