The Nazi-Soviet Pact and the Partition of Eastern Europe

The Collapse of Collective Security: the World the Soviet Union Faced by May 1939

On 3 May 1939, Stalin dismissed Maxim Litvinov as People's Commissar for Foreign Affairs and installed Vyacheslav Molotov in his place. This was no routine reshuffle. Litvinov had been the face of Soviet diplomacy since 1930 and the unwavering advocate, ever since the USSR joined the League of Nations in 1934, of 'collective security': the policy of containing fascist expansion through a common front with the Western democracies. His removal signalled, at home and abroad, that the policy itself had been abandoned.

Why had collective security failed? The answer is layered into the sequence of events that unfolded across Europe from Hitler's seizure of power in 1933.

Hitler pulled Germany out of the League of Nations (October 1933) and declared rearmament. In March 1936 his troops marched into the Rhineland; the Versailles system was dead on paper. When the Spanish Civil War erupted in July 1936, Germany and Italy backed Francisco Franco's insurgents, while the Soviet Union supported the Republican government. But Britain and France responded with a Non-Intervention Committee that effectively blockaded the legitimate Republic from buying arms. Spain became Europe in miniature for three years: fascism and anti-fascism at each other's throats, the Western democracies standing by in the name of 'neutrality'.

In November 1936, Germany and Japan concluded the Anti-Comintern Pact; Italy joined the following year. The Soviet Union now faced a strategic encirclement on two fronts, European and Far Eastern. Japan's full-scale invasion of China began in 1937, and in the summer of 1938 Soviet and Japanese forces clashed at Lake Khasan on the Manchurian border.

The decisive blow came in September 1938: the Munich Agreement. British Prime Minister Neville Chamberlain and French Premier Édouard Daladier summoned only Hitler and Mussolini to Munich; Czechoslovak representatives waited outside while their country was dismembered. The Soviet Union was not invited at all. The USSR had a mutual-assistance treaty with Czechoslovakia and was willing to fight if France acted first, but that option was foreclosed from the start. Munich can be reduced to a sentence: Britain and France had decided to push Hitler eastward, toward the Soviet Union.

Stalin told the 18th Party Congress in March 1939: 'The policy of non-intervention means conniving at aggression, giving free rein to war, and consequently transforming the war into a world war.' He added that the Soviet Union would not let itself be drawn into conflict by 'warmongers who are accustomed to have others pull the chestnuts out of the fire for them.' The 'chestnuts' were a direct retort to the Western press campaign speculating about a German 'march on Soviet Ukraine': the hope, barely concealed, that Hitler's next target would lie east. Stalin refused the bait.

By the spring of 1939 the Soviet position stood as follows. To the west, Hitler had occupied what remained of Czechoslovakia in March 1939, seized Memel (Klaipėda) from Lithuania on 23 March, and was pressing Poland over Danzig and the 'corridor.' Britain and France finally guaranteed Polish independence on 31 March, but remained lukewarm toward a real military alliance with the USSR. To the east, the Japanese Kwantung Army launched its offensive against Soviet-Mongolian forces at Khalkhin Gol on 11 May 1939. The Soviet Union faced the real risk of a two-front war.

Moreover, the Red Army's officer corps had been decimated by the Great Purge of 1937–1938. Marshal Mikhail Tukhachevsky and a large proportion of senior commanders had been shot or sent to camps. The Western powers rated Soviet military strength low, which was yet another reason London and Paris did not treat the Moscow negotiations seriously.

3 May 1939 was the point at which all those failures converged. Litvinov's dismissal declared that collective security was no longer the premise of Soviet diplomacy. Stalin now had two negotiating tables open: the triple-alliance military talks with Britain and France in Moscow, and the secret channel to Berlin. And the clock on his choice was ticking fast.

Litvinov's Dismissal and the Two Negotiating Tables

On 3 May 1939, Soviet Foreign Commissar Maxim Litvinov was summoned to Stalin's office. Stalin told him the Soviet government intended to improve relations with Hitler and, if possible, sign a pact with Nazi Germany. Litvinov, a Jew and the living symbol of the anti-German line, "stood in the way." When Litvinov banged the table in protest, Stalin demanded he sign a letter of resignation. That same night, NKVD troops surrounded the People's Commissariat for Foreign Affairs. The German chargé d'affaires, Werner von Tippelskirch, cabled Berlin: Molotov's appointment was trumpeted on the front page, but Litvinov's dismissal appeared as a small notice under "Chronicle" on the back. Berlin took note.

Litvinov had been the face of collective security since 1930. He had pleaded the anti-fascist cause at the League of Nations, signed mutual-assistance treaties with France and Czechoslovakia, and backed Republican Spain. The moment the USSR was excluded from the Munich Agreement (September 1938), his line suffered a mortal blow. When Hitler swallowed the rest of Czechoslovakia and annexed Memel in March 1939, Britain and France belatedly guaranteed Poland, Romania, and Greece and proposed talks with Moscow. But Moscow had not forgotten Munich.

Molotov was a different kind of figure: not a Jewish intellectual diplomat but a Russian party functionary, Stalin's "most intimate friend and closest collaborator," who kept his post as Chairman of the Council of People's Commissars (premier). At his first meeting with German Ambassador Schulenburg on 20 May, Molotov said that before economic talks could resume, the necessary "political basis" [politische Grundlage] had to be built. Berlin parsed the phrase carefully. On 30 May, State Secretary Weizsäcker minuted: "Now our answer: what does political basis mean?"

But Molotov was not focused solely on the German channel. In his Supreme Soviet speech on 31 May, he stated that the USSR saw "no need to renounce business relations with countries like Germany," yet also laid out three conditions for a pact with Britain and France: an effective mutual-assistance treaty, joint guarantees for all Central and East European states including the Baltic three, and a concrete military convention. These were Moscow's minimum terms for the genuine military alliance it wanted.

Britain and France spent the next two and a half months failing to meet them. The sticking points piled up: the definition of "indirect aggression," the refusal to guarantee the Baltic states, the insistence on League of Nations procedures. Soviet ambassador Ivan Maisky negotiated in London with Under-Secretary Vansittart to no avail. When Latvia and Estonia signed non-aggression pacts with Germany on 7 June, the Soviets' Baltic fears were made tangible. Moscow could not shake the suspicion that the British and French meant to drag the USSR into war with Germany while they themselves stood aside.

By mid-July the political talks had stalled, and Moscow demanded simultaneous military negotiations. Britain and France agreed on 23 July but sent their military missions by slow merchant ship; they reached Leningrad only on 9 August. The head of the British delegation, Admiral Sir Reginald Drax, carried no written negotiating authority, only instructions to prolong the talks. When the military discussions opened in Moscow on 12 August, Soviet Defence Commissar Voroshilov asked the first question: "Would the Red Army be allowed to cross into Poland and Rumania in the event of German aggression?" Polish Foreign Minister Józef Beck had already answered: "With the Germans we risk losing our liberty; with the Soviets, our soul." Britain and France, Poland's allies, did not press Warsaw to relent.

Three Days to a Deal: 19 to 23 August

During the very days when the military talks with Britain and France stalled over the question of passage through Poland, the German track accelerated in the opposite direction. Hitler's timetable drove the pace: the invasion of Poland was set for 26 August, and Soviet neutrality had to be secured before it. On 19 August the German-Soviet commercial and credit agreement was signed (a credit of 200 million marks against Soviet raw materials), and the same day Moscow agreed in principle to receive Ribbentrop. On 21 August Hitler cabled Stalin personally, asking that Ribbentrop be received "on 22 August, at the latest on 23 August"; Stalin replied within two hours. That night the three-power military talks in Moscow were adjourned indefinitely.

Ribbentrop arrived in Moscow on the afternoon of 23 August, and the first Kremlin session with Stalin and Molotov settled the framework in three hours. The treaty text was simple: mutual non-aggression, neutrality if either party found itself at war with a third power, a ten-year term. The core was the secret additional protocol signed with it. Finland, Estonia, Latvia and Romanian Bessarabia fell to the Soviet sphere of interest, Lithuania to the German one, and Poland was divided along the line of the Narew, Vistula and San. Point two of the protocol stated that "the question of whether the interests of both parties make desirable the maintenance of an independent Polish state, and how such a state should be bounded, can only be definitely determined in the course of further political developments." The very existence of the Polish state was treated as a matter for the two signatories to dispose of. The signing came after midnight, in the early hours of the 24th, though the document bears the date of the 23rd. At the banquet Stalin raised his glass to Hitler; according to the German record he said he knew "how much the German nation loves its Führer."

Dawn of 17 September: the Second Invasion

After Germany invaded Poland on 1 September, Berlin repeatedly pressed Moscow to move into its allotted share. Molotov did not hurry. On 5 September he replied that "the proper time has not yet come," and told the Germans that Soviet entry needed a justification: the collapse of the Polish state had made it necessary to protect the Ukrainians and Belorussians. With Warsaw encircled and the ceasefire with Japan at Khalkhin Gol taking effect on 16 September, both conditions were met. At 3 a.m. on 17 September Deputy Foreign Commissar Potemkin summoned the Polish ambassador Grzybowski and read him a note: the Polish government had ceased to exist, and the Soviet Union was sending in its army to protect the lives and property of the population of Western Ukraine and Western Belorussia. Grzybowski refused to accept the note.

The Belorussian and Ukrainian Fronts crossed the border. The Polish army's main forces were fighting the Germans in the west, and commander-in-chief Rydz-Smigly ordered his troops not to engage the Soviets except against attempts to disarm them. Apart from resistance at Grodno and a few other points, the advance was rapid. Wilno was taken on 19 September; on the 22nd Lwow surrendered to the Soviets, and the same day a joint parade marked the German handover of Brest-Litovsk. By the Soviet count 737 of their soldiers were killed; on the Polish side more than 3,000 died fighting the Red Army and some 230,000 were taken prisoner.

From Partition to Annexation

Once the Friendship and Boundary Treaty of 28 September fixed the demarcation line, the legal incorporation of the occupied zone, some 200,000 square kilometres with about 13 million inhabitants, was rushed through. On 22 October elections to the 'People's Assemblies' of Western Ukraine and Western Belorussia were held under NKVD supervision, on single candidate lists and in conditions close to open voting. The new assemblies immediately petitioned for admission to the USSR, and on 1 and 2 November the Supreme Soviet incorporated the two regions into the Ukrainian and Belorussian Soviet republics. A decree of 29 November imposed Soviet citizenship on all inhabitants. Wilno and its district had been handed to Lithuania on 10 October in exchange for a mutual assistance treaty that included Soviet bases; within a year Lithuania itself would be annexed.

Occupation: Deportations and Katyn

Sovietization began with annexation. Banks and industry were nationalized, and officials of the Polish state, army officers, policemen, landowners and osadniks (military settlers planted in the eastern borderlands in the 1920s) became targets of arrest. According to NKVD records, four mass deportations between February 1940 and June 1941 sent about 320,000 people to Siberia, Kazakhstan and the far north: some 140,000 osadniks and foresters on 10 February 1940, about 61,000 family members of arrested men on 13 April, about 78,000 refugees (many of them Jews) in June, and a final wave in May and June 1941. Transport and settlement conditions were brutal and mortality was high.

Among the prisoners of war, officers and policemen were concentrated in three special camps at Kozelsk, Starobelsk and Ostashkov. On 5 March 1940 Beria proposed to Stalin that 14,700 prisoners of war and 11,000 inmates of the prisons of Western Ukraine and Western Belorussia, whom he called "hardened, irremediable enemies of Soviet power," be examined by special procedure "without summoning those arrested and without presenting charges," applying "the supreme penalty: shooting." The Politburo adopted the proposal the same day; the first page of the note carries the signatures of Stalin, Voroshilov, Molotov and Mikoyan. In April and May 1940 about 21,857 people were shot at Katyn forest, in Kalinin (Tver), in Kharkov and elsewhere. This is the Katyn massacre. After the Germans uncovered the Katyn graves in 1943 the Soviet Union blamed them for half a century, and only on 13 April 1990 officially acknowledged the responsibility of the NKVD.

Completing the Protocol: the Baltics and Bessarabia

The partition of Poland was only the beginning. Between late September and early October 1939 the Soviet Union imposed mutual assistance treaties on Estonia (28 September), Latvia (5 October) and Lithuania (10 October), obtaining military bases in each. Nominally the three states kept their internal order; on 31 October Molotov told the Supreme Soviet that talk of their Sovietization was "foolish talk." The same demand went to Finland, which refused; the result was the Winter War that began on 30 November.

The turning point came in June 1940, when Germany was overrunning France and Europe's eyes were fixed on the west. On 14 June, the day Paris fell, the Soviet Union delivered an ultimatum to Lithuania; Latvia and Estonia followed on the 16th. The demands were identical: new governments that would honestly implement the mutual assistance treaties, and the admission of unlimited additional Soviet troops. All three complied without resistance and the Red Army occupied the countries. Zhdanov (Estonia), Vyshinsky (Latvia) and Dekanozov (Lithuania) were sent as plenipotentiaries to supervise the formation of the new governments. People's assemblies elected on 14 and 15 July on single candidate lists petitioned for admission to the USSR, following the script already used in occupied Poland, and Lithuania was incorporated as a Soviet republic on 3 August, Latvia on the 5th, Estonia on the 6th. The United States announced its non-recognition of the annexations in the Welles Declaration of 23 July; that non-recognition lasted until 1991.

Bessarabia's turn came in between. On 26 June the Soviet Union presented Romania with an ultimatum demanding the cession of Bessarabia together with northern Bukovina. Bessarabia had been assigned to the Soviet sphere by the protocol, but Bukovina was an extra demand not contained in it, and Berlin protested. Isolated, Romania yielded on the 28th and Soviet troops marched in. On 2 August most of Bessarabia was organized as the Moldavian Soviet Socialist Republic, while northern Bukovina and the southern coastal strip of Bessarabia went to the Ukrainian republic. Until June 1941 the Baltic states and Bessarabia went through the same nationalizations, arrests and deportations as occupied Poland; the Baltic deportation of 14 June 1941 alone, days before the German invasion, carried off about 40,000 people.

By the summer of 1941, of the territory the secret protocol had assigned to the Soviet sphere of interest, everything except Finland had become Soviet territory: some 23 million people in all.

How to Judge the Pact

The official Soviet explanation was codified in the 1948 Soviet Information Bureau pamphlet Falsifiers of History: once the West had tried at Munich to turn Hitler eastward, the pact was a forced defensive measure that kept the USSR out of a war between imperialist camps and bought time to prepare against invasion. The argument has substance. Collective security had been wrecked at Munich rather than abandoned by Moscow alone; the Anglo-French negotiating record was half-hearted enough to justify Soviet suspicion; and the pact gave the USSR twenty-two months and several hundred kilometres of depth.

Yet scholarship broadly agrees that the defensive logic does not close the account. Germany bought time too: spared a two-front war, it defeated Western Europe piecemeal, while Soviet grain and oil blunted the British blockade. The depth of the new frontier contributed almost nothing to the defence of June 1941. Above all, the secret protocol was not a promise of non-aggression but an advance distribution of the territory of third countries, and its implementation (the partition of Poland, the annexation of the Baltic states, Katyn and the deportations) cannot be subsumed under defence. The Soviet Congress of People's Deputies itself drew this distinction in December 1989: the non-aggression treaty could be seen as a product of the diplomatic practice of its time, but the secret protocol violated the sovereignty of third countries and Leninist principles of foreign policy, and was therefore "legally void from the moment of signing." Historians continue to argue whether the pact was a forced response or a chosen expansion, but on either reading it completed the conditions for the outbreak of the Second World War.

What the Pact Settled, and What It Did Not

The pact settled more than neutrality. The secret additional protocol of 23 August 1939 placed the future of the Baltic states and Finland in the Soviet sphere of influence, and divided the future of Poland between German and Soviet spheres along a line near the Narew, Vistula, and San rivers. It left the question of whether Poland would survive as an independent state to “further political developments” and ended by requiring that the arrangement be kept “strictly secret.” Alongside the public ten-year promise of non-aggression, the parties therefore treated the sovereignty of countries that belonged to neither of them as a matter for bilateral bargaining. The Boundary and Friendship Treaty of 28 September and its confidential protocols turned that draft into actual borders, occupation, and population transfers. Germany received the freedom to attack Poland without fearing a war with the Soviet Union; the USSR received time to move its frontier westward, hold German forces at a distance, and build a buffer. From the Soviet leadership’s standpoint, this was a calculation to postpone war and continue military preparation while fascist aggression in Europe coincided with the Japanese threat in Asia. That calculation must be understood from inside, because it explains why the agreement could appear persuasive in Moscow. But “a defensive agreement that bought time” cannot by itself explain coercion against eastern Poland and the Baltic states, the war against Finland, the seizure of Bessarabia and northern Bukovina, or deportations and executions under occupation. Germany’s betrayal in June 1941 ended the pact, but before then the territory gained by the USSR and the freedom of action gained by Germany had become facts.

The historical dispute is therefore not whether the pact produced aggressive consequences. The documents and subsequent actions establish that. The dispute concerns how wide Stalin’s available choices were and what kind of choice he made. One interpretation holds that Britain and France failed to create a reliable military agreement, while Poland refused Soviet troop transit, so an agreement with Germany was a harsh but rational act of national security by a government unwilling to stand alone. Another argues that Moscow used the collective-security talks to raise its price while already bargaining over the partition of Eastern Europe, making the protocol not a defensive line but an imperial transaction in which two dictatorships divided third countries. The Soviet Congress of People’s Deputies’ resolution of December 1989 offers a useful distinction. It acknowledged that the public treaty was signed in a crisis, with the aim of sheltering the USSR from looming war, but declared that the secret protocols violated the sovereignty and independence of third states and were legally invalid from the moment of signing. That judgment does not erase the Soviet search for security; it denies that security created a right to occupy others. Historians still differ over whether to give greater weight to an unavoidable breathing space or an opportunistic partition, but the two judgments can coexist. The pact gave the Soviet Union time, while forcibly taking that time away from the peoples of Eastern Europe. That double character is why the event remains unsettled.