The origins of the Cold War, including ideological differences, the wartime conferences at Yalta (February 1945) and Potsdam (July to August 1945), and the breakdown of the Grand Alliance

A 15-mark "to what extent" needs a clear judgement and weighted evidence.

Thesis

Yalta and Potsdam revealed rather than caused the breakdown. The underlying ideological gulf between Stalinist communism and Anglo-American liberal capitalism, plus the strategic vacuum left by Nazi Germany's defeat, drove the rupture; the conferences turned latent disagreement into explicit deadlock.

Yalta, 4 to 11 February 1945

Roosevelt, Churchill, and Stalin agreed Soviet entry into the Pacific war, the United Nations voting formula, the four-zone occupation of Germany, and the Declaration on Liberated Europe promising free elections. The compromises masked irreconcilable readings of "free elections" in Poland.

Potsdam, 17 July to 2 August 1945

Truman, Attlee (replacing Churchill mid-conference after the 26 July election), and Stalin met after Roosevelt's death (12 April 1945) and the successful Trinity test (16 July). Truman's tougher line, the news of the bomb, and Stalin's installed Lublin government in Poland turned bargaining into ultimatum.

Underlying causes

Ideological mistrust dating to 1917, the delayed Second Front (until June 1944), the wartime Lend-Lease cut-off (May 1945), and Soviet security demands in Eastern Europe predated the conferences.

Judgement

The conferences were the diplomatic theatre in which the breakdown became public; the causes were structural.

A 3-mark "outline" wants three distinct, correctly attributed agreements in a sentence each - not a narrative of the war.

The occupation of Germany

Germany (and Berlin) would be divided into four occupation zones - American, British, Soviet, and a French zone carved from the western shares.

Soviet entry into the Pacific war

The USSR agreed to declare war on Japan within three months of Germany's defeat, in return for territory in Manchuria and southern Sakhalin.

Liberated Europe and the UN

The Declaration on Liberated Europe promised "free elections" in liberated countries, and the United Nations would be founded with permanent Security Council vetoes.

Marking criteria

1 mark each for three distinct, correctly dated Yalta agreements; the Polish question was deferred, not settled, so do not list it as a firm agreement.

A 4-mark "explain" needs a cause-and-effect chain with dated specifics.

Roosevelt's death (12 April 1945)

Truman, vice-president for only 82 days and excluded from the Manhattan Project, succeeded him. His instinctive view of Stalin was harsher than Roosevelt's, replacing flexibility with bluntness; he briefly cut Lend-Lease on 12 May.

The Trinity test (16 July 1945)

The first atomic detonation succeeded the day before Potsdam opened, giving Washington a monopoly weapon. Truman mentioned a "new weapon of unusual destructive force" to Stalin on 24 July.

The effect

A tougher president plus an atomic monopoly hardened the American line at Potsdam, turning the bargaining of Yalta into something closer to ultimatum just as Stalin's grip on Poland tightened.

Marking criteria

1 mark for the succession and Truman's harder line; 1 mark for the Trinity date/monopoly; 1 mark for linking each to the changed atmosphere; 1 mark for tying both to Potsdam's deadlock.

A 5-mark "explain ... using the source" wants the source decoded, then linked to own knowledge.

Decode the source

The wording is deliberately elastic. "Broadly representative" and "free and unfettered elections" meant liberal multi-party democracy to Roosevelt and Churchill, but to Stalin meant governments "friendly" to Moscow - and the Declaration committed no enforcement mechanism.

Own knowledge

The test case was Poland. Stalin had already installed the Lublin Committee (July 1944) as the de facto government against the London government in exile. Yalta only agreed it would be "reorganised on a broader democratic basis," and by Potsdam the Lublin government was provisionally recognised with no date set for elections.

The outcome

With Soviet armies physically occupying the region and no Anglo-American leverage to compel free elections, the same text was read as a democratic promise in Washington and as cover for a security buffer in Moscow.

Marking criteria

1-2 marks for identifying the ambiguity and absence of enforcement in the source; 1-2 marks for own knowledge on Poland (London vs Lublin); 1 mark for the conclusion that occupation made the Western reading unenforceable.

A 6-mark "assess the usefulness" of two sources rewards origin/perspective for each, corroboration from own knowledge, and a comparative judgement.

Source B - perspective and use

This is the revisionist case (Alperovitz, Atomic Diplomacy, 1965): the bomb as a message to Moscow. It is useful for explaining the hardening American line and the timing - the Trinity test (16 July) preceded Potsdam, and Truman did mention the "new weapon" to Stalin. Its limitation is that it can overstate intent and downplay Japanese-theatre military reasons for the bombings.

Source C - perspective and use

This is the post-archive view (later Gaddis, We Now Know, 1997; Zubok, A Failed Empire, 2007), built on opened Soviet archives. It is useful because it corrects the revisionist case with documentary evidence that Stalin, informed by intelligence (Fuchs), had already decided on an exclusive sphere. Its limitation is hindsight bias and the danger of reducing a structural conflict to one man's pathology.

Corroboration from own knowledge

Both fit parts of the record: the Lend-Lease cut (12 May), the Lublin government, and Stalin's "two camps" speech (Feb 1946) support C; the atomic monopoly and Truman's tougher line support B.

Judgement

Together they are more useful than either alone: B explains the American instruments, C explains Soviet intent. The post-archive evidence (C) carries more weight on causation, but B remains valuable for the diplomacy of the bomb. Useful, but each must be read against the other.

Marking criteria

1 mark each for correctly identifying the revisionist and post-archive perspectives; 1-2 marks for usefulness and a limitation of each; 1 mark for own-knowledge corroboration; 1 mark for a comparative judgement.

This is an extended-response/essay. Markers reward a sustained, evidence-based argument that addresses "to what extent" directly and sets historians in genuine tension - not a narrative of the two conferences.

Band-6 PLAN

• Thesis. The conferences revealed rather than caused the breakdown. The underlying ideological gulf, the strategic vacuum left by Nazi Germany's defeat, and Stalin's security demands drove the rupture; Yalta and Potsdam were the diplomatic theatre in which latent disagreement became explicit deadlock. They mattered as accelerants, not as the root cause.
• Argument 1 - The structural causes predated the conferences. Ideological enmity ran back to 1917 and the 1918-1920 Allied intervention; wartime grievance (the Second Front delayed until June 1944, the Lend-Lease cut of May 1945) had already eroded trust; and the defeat of Germany and Japan created a power vacuum two superpowers were bound to contest. Evidence: Soviet resentment of the delayed Normandy landing; 27 million Soviet dead driving the demand for a buffer.
• Argument 2 - Yalta papered over the cracks (a compromise, not a cause). At Yalta (4-11 Feb 1945) the Big Three agreed German zones, the UN veto, Soviet entry into the Pacific war, and the Declaration on Liberated Europe. But the Polish question was deferred and "free elections" left undefined; the compromise masked irreconcilable readings rather than resolving them.
• Argument 3 - Potsdam recorded the deadlock as personnel and power shifted. By Potsdam (17 Jul-2 Aug 1945) Roosevelt was dead, Truman tougher, Attlee had replaced Churchill, and the Trinity test (16 Jul) gave Washington an atomic monopoly while Stalin's Lublin government was entrenched. Bargaining became ultimatum: Poland's elections went unspecified, reparations split by zone. The conferences exposed, but did not invent, the divide.
• Historiography. The orthodox school (Schlesinger, Feis) blames Stalin's expansionism - the conferences as the moment his bad faith showed. The revisionist school (Williams, Alperovitz) blames American economic and atomic diplomacy - Potsdam as the start of intimidation. The post-revisionist school (early Gaddis, Leffler) treats the breakdown as the structural product of two superpowers in the 1945 vacuum. The post-archive Gaddis (We Now Know, 1997) and Zubok (A Failed Empire, 2007) returned weight to Stalin's ideology and paranoia.
• Judgement. Set orthodox/post-archive (Stalin's intent) against revisionist (American instruments) and resolve through the post-revisionist structural frame: the conferences were necessary stages where the rupture became public, but the decisive causes - ideology, the vacuum, and Stalin's security drive - lay beneath and before them. To a limited extent, then: the conferences accelerated and exposed the breakdown; they did not cause it.

MODEL PARAGRAPH (Argument 3)

Potsdam is best read not as the cause of the rupture but as the conference at which the breakdown was recorded. By the time the Big Three met at the Cecilienhof on 17 July 1945, three things had changed since Yalta: Roosevelt was dead and Truman, blunter and already suspicious, had briefly cut Lend-Lease in May; Churchill was replaced mid-conference by Attlee; and the Trinity test of 16 July had handed Washington a monopoly weapon, which Truman alluded to on 24 July. Against this, Stalin's Lublin government was already installed in Poland and no date for "free elections" was fixed. The result was a conference of ultimatums rather than bargains - reparations split crudely by zone, the Oder-Neisse border imposed, the Council of Foreign Ministers left to mop up. As John Lewis Gaddis argues in his post-archive We Now Know (1997), the documentary record returns the initiative to Stalin, whose determination on a security sphere predated Potsdam; the revisionist reading of Gar Alperovitz (Atomic Diplomacy, 1965), that the bomb was brandished to intimidate Moscow, captures the American instruments but not the deeper Soviet intent. Potsdam, on this view, displayed a breakdown already structurally complete.

Marker's note. A band-6 response keeps "to what extent" in view throughout - ranking the conferences against the structural causes rather than narrating Yalta then Potsdam - anchors every claim in dated specifics (the Trinity test, the Lublin government, the Lend-Lease cut), and deploys at least two historians in genuine tension (orthodox/post-archive Stalin-blame vs revisionist American-diplomacy). Reaching a graded judgement ("revealed rather than caused") rather than listing factors is what lifts the response into the top band.

This is an extended-response/essay. Markers reward a sustained argument that weighs ideology against other causes (security, the atomic bomb, personality) and sets historians in genuine tension - not a narrative of the conferences.

Band-6 PLAN

• Thesis. Ideology was a necessary condition of the breakdown but not a sufficient one: the Marxist-Leninist conviction that capitalism and communism could not permanently coexist shaped Stalin's distrust and his demand for a buffer, yet that ideology became decisive only because it fused with concrete security fears and the strategic vacuum of 1945. Ideology framed the conflict; security and circumstance triggered it.
• Argument 1 - Ideology as the deep frame. The enmity ran back to 1917 and the Allied intervention of 1918-1920; Marxism-Leninism predicted inevitable conflict between the systems, and Stalin's 9 February 1946 "two camps" speech revived the thesis that capitalist contradictions would breed new wars. American liberalism (the 1941 Atlantic Charter, the 1945 UN Charter) encoded free markets, free elections and self-determination as universal - so each side read the other's normal conduct as aggression. Evidence: the clash over "free elections" in the Declaration on Liberated Europe.
• Argument 2 - Security and circumstance, not pure ideology. Stalin's demand for "friendly governments" rested on 27 million Soviet dead and a repeatedly invaded western frontier; the buffer was a strategic calculation a non-communist Russian state might also have made. The atomic monopoly (Trinity, 16 July) and Truman's tougher line were contingent, not ideological. Evidence: the Lend-Lease cut (12 May); Soviet entry into the Pacific war traded for territory.
• Argument 3 - Ideology and security fused at the decisive points. In Poland the two were inseparable: a "friendly" government was simultaneously an ideological asset and a security buffer, and the Red Army's occupation made Western objections unenforceable. Ideology supplied the lens; the post-war vacuum supplied the opportunity.
• Historiography. The orthodox school (Schlesinger, Feis) makes Stalin's ideology and expansionism the cause. The revisionist school (Williams, Alperovitz) downplays Soviet ideology and blames American economic and atomic diplomacy. The post-revisionist school (early Gaddis, Leffler) treats ideology as one factor in a structural security dilemma of mutual misperception. The post-archive Gaddis (We Now Know, 1997) and Zubok (A Failed Empire, 2007), using Soviet records, restore ideology and Stalin's "revolutionary-imperial" outlook to the centre.
• Judgement. Weigh the post-archive emphasis on Stalin's ideology against the revisionist stress on American instruments and the post-revisionist security dilemma: ideology was the indispensable frame that turned ordinary great-power friction into an irreconcilable contest, but it required the security fears and the 1945 vacuum to produce the rupture. Important, even primary as a frame - decisive on its own, no.

MODEL PARAGRAPH (Argument 3)

The Polish question shows that ideology and security were not rival explanations but a single fused cause. For Stalin a government in Warsaw "friendly" to Moscow was at once an ideological gain - a fellow socialist-leaning state extending the revolution's perimeter - and a hard security asset closing the corridor through which Germany had twice invaded. The two motives pointed to the same policy, which is why the Lublin Committee was installed (July 1944) and entrenched well before either conference could settle the issue. The Anglo-American insistence on "free and unfettered elections" was, from Moscow's view, both an ideological threat (liberal democracy on the Soviet doorstep) and a strategic one (a potentially hostile buffer), and the Red Army's physical occupation made Western objection toothless. As the post-archive John Lewis Gaddis argues in We Now Know (1997), the opened records reveal an ideology that made compromise psychologically impossible for Stalin; against this, the revisionist Gar Alperovitz (Atomic Diplomacy, 1965) foregrounds American pressure but cannot explain why Stalin treated even modest Western demands as existential. In Poland, ideology and security spoke with one voice.

Marker's note. A band-6 response defines "ideology" and weighs it explicitly against security, circumstance and personality rather than asserting it; anchors each claim in dated evidence (the "two camps" speech, the Lublin Committee, the Lend-Lease cut); and sets at least two historians in genuine tension (post-archive ideology-centred Gaddis/Zubok vs revisionist American-diplomacy Williams/Alperovitz, mediated by the post-revisionist security dilemma). A graded judgement - ideology as indispensable frame rather than sole cause - lifts the response into the top band.