Military occupations by the Soviet Union
During World War II, the Soviet Union occupied and annexed several countries allocated to it in the secret Molotov–Ribbentrop Pact of 1939. These included the eastern regions of Poland, as well as Latvia, Estonia, Lithuania, part of eastern Finland and eastern Romania. Apart from the Molotov–Ribbentrop Pact and post-war division of Germany, the Soviets also occupied and annexed Carpathian Ruthenia from Czechoslovakia in 1945. These occupations lasted until the dissolution of the Soviet Union in 1990 and 1991.
Below is a list of various forms of military occupations by the Soviet Union resulting from both the Soviet pact with Nazi Germany, and the ensuing Cold War in the aftermath of Allied victory over Germany.
Poland (1939–1956)
Poland was the first country to be occupied by the Soviet Union during World War II. The secret protocol of the Molotov–Ribbentrop pact stipulated Poland to be split between Soviet Union and Nazi Germany. In 1939, the total area of Polish territories occupied by the Soviet Union, was 201,015 square kilometres, with a population of 13.299 million, of which 5.274 million were ethnic Poles and 1.109 million were Jews.After the end of World War II, the Soviet Union kept most of the territories it occupied in 1939, while territories with an area of 21,275 square kilometers with 1.5 million inhabitants were returned to communist-controlled Poland, notably the areas near Białystok and Przemyśl. In 1944–1947, over a million Poles were resettled from the annexed territories into Poland.
Soviet troops were stationed in Poland from 1945 until 1993. It was only in 1956 that official agreements between the communist regime in Poland established by the Soviets themselves and the Soviet Union recognized the presence of those troops; hence some Polish scholars accept the usage of the term 'occupation' for the period spanning 1945–1956. The Polish government-in-exile existed until 1990.
Baltic states (1940–1991)
, Latvia, and Lithuania had been independent nations since 1918, when all three countries were occupied by the Red Army in June 1940 and formally annexed into the USSR in August 1940. Given a free hand by Nazi Germany via the German–Soviet Nonaggression Pact and its secret additional protocol of August 1939, the Soviet Union pressured the three countries to accept its military bases in September 1939. In the case of refusal, the USSR effected an air and naval blockade and threatened to attack immediately with hundreds of thousands of troops massed upon the border. The Soviet military forces overtook the political systems of these countries in June 1940 and installed puppet regimes after rigged elections in July 1940.The sovietisation was interrupted by the German occupation in 1941–1944. The Baltic Offensive re-established the Soviet control in 1944–1945, and resumed sovietisation, mostly completed by 1950. The forced collectivisation of agriculture began in 1947, and was completed after the mass deportation in March 1949. Private farms were confiscated, and farmers were made to join the collective farms. An armed resistance movement of 'forest brothers' was active until the mid-1950s. Hundreds of thousands participated or supported the movement; tens of thousands were killed. The Soviet authorities fighting the forest brothers also suffered hundreds of deaths. Some innocent civilians were killed on both sides. In addition, a number of underground nationalist schoolchildren groups were active. Most of their members were sentenced to long terms of imprisonment. The punitive actions decreased rapidly after Joseph Stalin's death in 1953; from 1956 to 1958, a large part of the deportees and political prisoners were allowed to return.
During the occupation, the Soviet authorities killed, politically arrested, unlawfully drafted, and deported hundreds of thousands of people. Numerous other kind of crimes against humanity were committed all through the occupation period. Furthermore, trying to enforce the ideals of Communism, the authorities deliberately dismantled the existing social and economic structures, and imposed new "ideologically pure" hierarchies. This severely retarded the Baltic economies. For example, Estonian scientists have estimated economic damages directly attributable to the post-World War II occupation to hundreds of billions of US dollars.
After all, the attempt to integrate the Estonian society into the Soviet system failed. Although the armed resistance was defeated, the population remained anti-Soviet. This helped the Estonians to organise a new resistance movement in the late 1980s, regain their independence in 1991, and then rapidly develop a modern society.
Notwithstanding the annexation by the Soviet Union in 1940, it is therefore correct to speak of the occupation of the Baltic states, referring in particular to the absence of Soviet legal title. The prolonged occupation was an unorthodox one. Until 1991, the status of the three countries resembled the classical occupation in important ways: external control by an internationally unsanctioned force and a conflict of interest between the foreign power and the inhabitants. However, in other aspects the situation was very different from a classical occupation. Both the fact of the incorporation of the Baltic states to the USSR as Soviet republics without qualification, and the long duration of the Soviet rule challenge the applicability of all rules on occupation from the practical point of view. Despite the fact of annexation, the presence of the USSR in the Baltic states remained an occupation sui generis.
Although the Soviet Union condemned the Molotov–Ribbentrop Pact—the immediate forerunner to the occupation—it is currently the policy of the USSR's legal successor Russian Federation to deny that the events constituted occupation or were illegal under applicable laws.
Finnish territories (1940)
After the Baltic states agreed to Soviet demands in September and October 1939, the Soviets turned their attention to Finland. The Soviet Union demanded territories on the Karelian Isthmus, the islands of the Gulf of Finland, a military base near the Finnish capital, and the destruction of all defensive fortifications on the Karelian Isthmus. Finland refused these demands. On 30 November 1939 the Soviet Union thus invaded the country, initiating the Winter War with the goal of annexing Finland. The USSR set up the Finnish Democratic Republic, a short-lived Soviet puppet regime in the occupied town of Terijoki. The Soviets also occupied the Petsamo municipality in the Barents Sea coast during the war.The Winter War ended on 13 March 1940 with the signing of the Moscow Peace Treaty. Finland retained its independence but ceded parts of Karelia, Salla, the Rybachy Peninsula in the Barents Sea, and four islands in the Gulf of Finland The land accounted for 9% of the country's territory, included the important city of Viipuri, and much of Finland's industry. About 422,000 Karelians — 12% of Finland's population — chose to evacuate beyond the new border and lose their homes rather than become Soviet subjects. The military troops and the remaining civilians were hastily evacuated.
When the hostilities resumed in 1941, Finnish forces retook the lost areas and then advanced further up to the Svir River and Lake Onega before the end of the year. In the Soviet offensive of 1944 against the Finns the Red Army advance was halted by the Finns before reaching the 1940 border or, in the sole case where it did happen, the Red Army was promptly thrown back in the Battle of Ilomantsi. In the negotiations that followed, the Finns ceded the Petsamo municipality to the Soviet Union in the Moscow Armistice.
Bessarabia and Northern Bukovina (1940)
The Soviet Union, which did not recognize the sovereignty of Romania over Bessarabia since the union of 1918, issued an ultimatum on 28 June 1940 demanding the evacuation of the Romanian military and administration from the territory it contested as well as from the northern part of the Romanian province of Bukovina. Under pressure from Moscow and Berlin, the Romanian administration and armed forces retreated to avoid war. Adolf Hitler used Soviet occupation of Bessarabia as justification for German occupation of Yugoslavia and Greece and German attack on USSR.After the Soviet Union entered the war on the Allied side
On 22 June 1941, the Operation Barbarossa commenced, which gave a start of the Eastern front. German-led European Axis countries and Finland invaded the USSR, thereby terminating the German-Soviet non-aggression treaty. During the hostilities between the Soviet Union and the Axis, which led to the total military defeat of the latter, the USSR fully or partially occupied the territory of Germany and its satellites, as well as the territories of some German-occupied states and Austria. Some of them became Soviet Satellite states, namely, the People's Republic of Poland, the People's Republic of Hungary, the Czechoslovak Socialist Republic, the Romanian People's Republic, the People's Republic of Bulgaria, the People's Republic of Albania; later, East Germany was formed based on the Soviet zone of German occupation.Iran (1941–1946)
On 25 August 1941 British and Commonwealth forces and the Soviet Union jointly invaded Iran. The purpose of the invasion was to secure Iranian oil fields and ensure supply lines for the Soviets fighting against European Axis countries on the Eastern Front. The Soviet Union would go on to set up the Azerbaijan People's Government in Iranian Azerbaijan while just occupying the rest of north Iran.Hungary (1944–1991)
In July 1941, the Kingdom of Hungary, a member of the Tripartite Pact, took part in Operation Barbarossa, in alliance with Nazi Germany. Hungarian forces fought shoulder to shoulder with the Wehrmacht and advanced through the Ukrainian SSR deep into Russia, all the way to Stalingrad. However, by the end of 1942 the Soviet Red Army began pushing back the Wehrmacht through a series of offensives that preceded the Red Army's encroachment upon Hungarian territory in 1943–44. In September 1944 Soviet forces crossed into Hungary, launching the Budapest Offensive. As the Hungarian army ignored the armistice with the USSR signed by the government of Miklós Horthy on 15 October 1944, the Soviets fought their way further westward against the Hungarian troops and their German allies capturing the capital on 13 February 1945. Operations continued until early April 1945, when the last German forces and their remaining loyal Hungarian troops were routed out of the country.Stalin's regime made sure that a loyal post-war government dominated by Communists was installed in the country before transferring authority from the occupational force to the Hungarian authorities. The presence of Soviet troops in Hungary was regulated by the 1949 mutual assistance treaty concluded between the Soviet and Hungarian governments.
The Hungarian Revolution of 1956 was a spontaneous nationwide revolt against the Communist government of Hungary and its Soviet-imposed policies. The Soviet Politburo announced or pretended a willingness to negotiate the withdrawal of Soviet forces in Hungary.
On 1 November 1956, Hungarian Prime Minister Imre Nagy declared Hungary's withdrawal from the Warsaw Pact.
On 4 November 1956, a large joint military force of the Warsaw Pact led by the Khrushchev regime entered Budapest to crush the resistance, killing thousands of civilians in the process.
About 200,000 Hungarians fled across the border to Austria, the only border of Hungary to the Western world.
On 19 June 1991, half a year before the dissolution of the Soviet Union, the last Soviet soldier left Hungary.