Your guide to the Yalta and Potsdam conferences, 1945

The so-called ‘big three’ convened at Livadia Palace, the former summer residence of Tsar Nicholas II, for eight days. Roosevelt, who was in poor health, had suggested a meeting place somewhere in the Mediterranean, but Stalin, who was famously afraid of flying, had refused to go farther than the Black Sea and suggested the Soviet resort of Yalta.

What was happening elsewhere in February 1945?

The Yalta Conference took place at a critical time in World War Two. By the start of 1945 it was clear that, despite continuing resistance, Germany had lost the war. The Battle of the Bulge – the last German offensive on the western front, fought in the Ardennes region of Belgium – had shattered what remained of the German army, as well as destroying essential weapons, tanks and supplies. Elsewhere, Stalin’s Red Army had captured East Prussia and was less than 50 miles from Berlin. The once mighty Luftwaffe was drastically depleted, while Allied bombs continued to fall on German towns and cities on a daily basis. Adolf Hitler was fighting a losing battle.

What did each of the 'big three' want from the meeting?

The three leaders had met 15 months earlier in the Iranian capital Tehran, where they had discussed ways to defeat Nazi Germany, agreed on an invasion of Normandy and had conversations around the Soviets’ entry into the Pacific War. The tentative beginnings of what a future peace settlement might look like had been made in Tehran, but it was at Yalta where the real discussions began.

Each leader sat down at Yalta with specific goals in mind. For Roosevelt, ending the ongoing war with Japan was of paramount importance, but to achieve this, he needed Stalin’s military help. The US president also wanted the Soviets to join the UN – a new global peacekeeping body – which it did, remaining a member until the collapse of the Soviet Union in 1991.

What elements of the Second World War are we in denial about? Keith Lowe explains – in 60 seconds

Stalin’s priority at Yalta was to get his country back on its feet and increase its standing on the European political stage. The Soviet Union, whilst crushing German forces on the eastern front, had been devastated by the war, with an estimated 27 million Soviet citizens (around one in seven) killed during the conflict, and vast swathes of industry, farming, cities and homes obliterated. Stalin needed money to rebuild his battered country, and pressed for huge reparations from Germany, as well as spheres of influence in Eastern Europe to prevent further invasions, and ensure that Germany could never threaten world peace again.

• Read more | A dictator’s death: how Stalin, Hitler, Mao and other self-styled strongmen met their ends

Churchill, too, was keen to see an end to any future German threat, but he was also concerned about extending the power of the USSR and wanted to see fair and free government across Eastern Europe, especially in Poland,
in whose defence Britain had declared war with Germany in 1939. Both he and Truman were worried that inflicting huge reparations on Germany, as had been done after World War I, could, in the future, create a similar economic situation in the country that had led to the rise and acceptance of the Nazi Party. With differing priorities and world views, it was clearly going to be difficult for the Big Three to reach an agreement.

Why wasn't French leader Charles de Gaulle present at the conference?

De Gaulle, by unanimous consent from all three leaders, was not invited to Yalta, nor to the Potsdam Conference a few months later; it was a diplomatic slight that created deep and lasting resentment. Stalin in particular felt that decisions about the future of Europe should be made by those powers who had sacrificed the most in the war. If France was allowed to participate at Yalta, other nations, too, would arguably have had an equal right to attend.

• Listen| Richard J Evans responds to listener queries and popular search enquiries about the Third Reich

What was eventually agreed at Yalta?

The decisions made at Yalta demonstrate the extent to which power had shifted between the Allies over the course of the war. Once Germany’s unconditional surrender had been received, it was proposed that the country, and its capital, be split into four occupied zones – the fourth occupation zone was granted to France but, at Stalin’s insistence, would
be formed out of the American and British zones.

• Read more | A brief guide to the Nuremberg Trials, where some Nazis faced justice after WW2

The fate of Poland was a key sticking point in negotiations. For centuries, the country had been used as a historical corridor for armies intent on invading Russia, and Stalin was determined to retain the regions of Poland that he had annexed in 1939 after the Soviet invasion. But he conceded to Churchill’s demand that free elections be held in all Nazi- liberated territories in Eastern Europe, including Czechoslovakia, Hungary, Romania, Bulgaria, and Poland.

Other key decisions included the demilitarisation of Germany; the payment of reparations by Germany, partly in the form of forced labour; the representation of two of the 16 Soviet Socialist Republics (Ukraine and Byelorussia) at the UN, and Soviet participation in the war against Japan, following Germany’s surrender. Another concession made by the US and Britain was to allow all former Soviet prisoners of war, including those who had changed sides and fought for Germany, to be forcibly repatriated back to the USSR.

• Read more | Aftermath of the Holocaust: how Europe dealt with the crimes of the Third Reich

What happened next?

None of the Big Three left Yalta with everything they had set out to achieve, but a public show of unity and cooperation was widely reported as they went their separate ways. At the conclusion of the conference, an agreement was made that they would meet once more after Germany had surrendered, so that they could make firm decisions on any outstanding matters, including the borders of post-war Europe. This final meeting took place at Potsdam, near Berlin, between 17 July and 2 August 1945.

What had happened between the ending of the Yalta conference and the meeting at Potsdam?

Aside from Germany’s surrender in May 1945, the political landscape had changed considerably in the five months that had passed since Yalta. Roosevelt, who had been seriously ill at Yalta, had died of a massive brain haemorrhage in April 1945, so it was the new US President Harry Truman who travelled to Berlin, accompanied by his newly appointed Secretary of State James Byrnes.

Promises made at Yalta had also been rescinded. Despite pledging free Polish elections, Stalin was already making moves to install a communist government in that country and many Poles, both in Britain and elsewhere, felt they had been sold out by Truman and Churchill. And despite the Pacific War that was still raging in the East, Stalin had not yet declared war on Japan or provided military support to the US.

• Read more | What was the Truman Doctrine?

What was different about the Potsdam conference?

The political atmosphere at Potsdam was decidedly more strained than at Tehran and Yalta. President Truman was far more suspicious of Stalin and his motives than Roosevelt, who had been widely criticised in the US for giving into Stalin’s demands over Poland and Eastern Europe. Truman was also open in his dislike of communism and Stalin personally, stating that he was “tired of babying the Soviets”.

Further upheaval was to come, though, with the results of the British general election, which had taken place on 5 July. The announcement, made three weeks later on 26 July (to allow the votes of those serving overseas to be counted) saw a decisive victory for the Labour Party and meant that Churchill and his Foreign Secretary Anthony Eden were replaced at the conference – from 28 July – by Britain’s new Prime Minister Clement Attlee and his Foreign Secretary Ernest Bevin. And although war against Japan was still ongoing, the lack of a common European enemy saw the Big Three find it harder to reach a mutually acceptable compromise on what the post-war political reconstruction of Europe would look like.

Another important development had also occurred since Yalta – one that would have a profound global impact. A week into the conference, after gaining Stalin’s agreement that the Soviets would join the Pacific War, Truman casually informed Stalin that the US was in possession of “a new weapon of unusual destructive force”: the atomic bomb, which had been tested for the first time on 16 July.

What was finally decided at Potsdam?

Once again, the fate of post-war Poland proved to be one of the biggest stumbling blocks of the conference, and it was finally agreed that Stalin would retain the land he had annexed in 1939. By way of compensation for land lost to the USSR, Poland was to be granted large areas of Germany, up to the Oder-Neisse Line – the border along the Rivers Oder and Neisse. But there was still no firm agreement that Stalin would adhere to his Yalta promise and ensure free elections in Eastern Europe.

As had been discussed at Yalta, Germany and Berlin were to be divided into four zones, with each Allied power receiving reparation from its own occupation zone – the Soviet Union was also permitted to 10- 15 per cent of the industrial equipment in the western zones of Germany in exchange for agricultural and other natural products from its own zone.

• Read more | "Many of the Holocaust's perpetrators got away with it": why Nazi crimes went unpunished

With regards to Germany itself, it was confirmed that administration of that country was to be dictated by the ‘five Ds’: demilitarisation, denazification, democratisation, decentralisation and deindustrialisation, and Germans living in Poland, Hungary and Czechoslovakia at the end of the World War II were to be forcibly expelled to Germany. Thousands of Germans died as a result of the expulsion order; official West German accounts state that at least 610,000 Germans were killed in the course of the expulsions. By 1950, the total number of Germans who had left eastern Europe (either voluntarily or by force) had reached 11.5 million.

A week into the conference, Truman casually informed Stalin that the US was in possession of the atomic bomb

Did Potsdam succeed in its aims with regard to Europe?

Although some agreements and compromises emerged at Potsdam, there were still important issues that had not been resolved. Before long, the Soviet Union had reconstituted the German Communist Party in the Eastern Sector of Germany and had begun to lay the groundwork for a separate, East German nation state, modelled on that of the USSR.

• Read more | How and when did the Second World War end?

What was the Potsdam declaration?

Though Germany was the focus at Potsdam, on 26 July the US, Britain and China issued the Potsdam Declaration: an ultimatum calling for the unconditional surrender of Japan. Stalin, not being at war with Japan, was not party to it. The Japanese did not surrender, and just days after the conference ended, the US dropped atomic bombs on Hiroshima and Nagasaki – which ultimately did what the Potsdam Declaration could not. Within weeks, Stalin had accelerated his own nuclear weapons programme, detonating its first atomic bomb – First Lightning – at a remote test site in Kazakhstan on 29 August 1949. The stage for the Cold War had been set.

This guide first appeared in BBC History Revealed