paragraph_text: Trotsky, and others, believed that the revolution could only succeed in Russia as part of a world revolution. Lenin wrote extensively on the matter and famously declared that Imperialism was the highest stage of capitalism. However, after Lenin's death, Joseph Stalin established 'socialism in one country' for the Soviet Union, creating the model for subsequent inward looking Stalinist states and purging the early Internationalist elements. The internationalist tendencies of the early revolution would be abandoned until they returned in the framework of a client state in competition with the Americans during the Cold War. With the beginning of the new era, the after Stalin period called the "thaw", in the late 1950s, the new political leader Nikita Khrushchev put even more pressure on the Soviet-American relations starting a new wave of anti-imperialist propaganda. In his speech on the UN conference in 1960, he announced the continuation of the war on imperialism, stating that soon the people of different countries will come together and overthrow their imperialist leaders. Although the Soviet Union declared itself anti-imperialist, critics argue that it exhibited tendencies common to historic empires. Some scholars hold that the Soviet Union was a hybrid entity containing elements common to both multinational empires and nation states. It has also been argued that the USSR practiced colonialism as did other imperial powers and was carrying on the old Russian tradition of expansion and control. Mao Zedong once argued that the Soviet Union had itself become an imperialist power while maintaining a socialist façade. Moreover, the ideas of imperialism were widely spread in action on the higher levels of government. Non Russian Marxists within the Russian Federation and later the USSR, like Sultan Galiev and Vasyl Shakhrai, considered the Soviet Regime a renewed version of the Russian imperialism and colonialism.

paragraph_text: The PTBT was signed by the governments of the Soviet Union, United Kingdom, and United States in Moscow on 5 August 1963 before being opened for signature by other countries. The treaty formally went into effect on 10 October 1963. Since then, 123 other states have become party to the treaty. Ten states have signed but not ratified the treaty.

paragraph_text: With an area of 2,700,000 square kilometres (1,000,000 sq mi) – equivalent in size to Western Europe – Kazakhstan is the ninth-largest country and largest landlocked country in the world. While it was part of the Soviet Union, Kazakhstan lost some of its territory to China's Xinjiang autonomous region and some to Uzbekistan's Karakalpakstan autonomous republic.

paragraph_text: Under the 1977 Constitution of the Union of Soviet Socialist Republics (USSR), the Chairman of the Council of Ministers was the head of government and the Chairman of the Presidium of the Supreme Soviet was the head of state. The office of the Chairman of the Council of Ministers was comparable to a prime minister in the First World, whereas the office of the Chairman of the Presidium was comparable to a president in the First World. In the Soviet Union's seventy - year history there was no official leader of the Soviet Union office, but during most of that era there was a de facto top leader who usually led the country through the office of the Premier or the office of the General Secretary of the Communist Party of the Soviet Union (CPSU). In the ideology of Vladimir Lenin the head of the Soviet state was a collegiate body of the vanguard party (see What Is to Be Done?).

paragraph_text: Dagda () is a town in eastern Latvia, near the country's border with Belarus. It is the administrative center of Dagda municipality.

paragraph_text: The Soviet Union created the Eastern Bloc of countries that it occupied, annexing some as Soviet Socialist Republics and maintaining others as satellite states that would later form the Warsaw Pact. The United States and various western European countries began a policy of "containment" of communism and forged myriad alliances to this end, including NATO. Several of these western countries also coordinated efforts regarding the rebuilding of western Europe, including western Germany, which the Soviets opposed. In other regions of the world, such as Latin America and Southeast Asia, the Soviet Union fostered communist revolutionary movements, which the United States and many of its allies opposed and, in some cases, attempted to "roll back". Many countries were prompted to align themselves with the nations that would later form either NATO or the Warsaw Pact, though other movements would also emerge.

paragraph_text: Previously, Moldovan athletes competed as part of the Soviet Union at the Olympics from 1952 to 1988, and after the dissolution of the Soviet Union, Moldova was part of the Unified Team in 1992.

paragraph_text: On 27 October 1981, a Whiskey-class submarine (U 137) from the Soviet Union ran aground close to the naval base at Karlskrona in the southern part of the country. Research has never clearly established whether the submarine ended up on the shoals through a navigational mistake or if an enemy committed espionage against Swedish military potential. The incident triggered a diplomatic crisis between Sweden and the Soviet Union. Following the 1986 assassination of Olof Palme and with the end of the Cold War, Sweden has adopted a more traditional foreign policy approach. Nevertheless, the country remains active in peace keeping missions and maintains a considerable foreign aid budget.

paragraph_text: Italy became a major industrialized country again, due to its post-war economic miracle. The European Union (EU) involved the division of powers, with taxation, health and education handled by the nation states, while the EU had charge of market rules, competition, legal standards and environmentalism. The Soviet economic and political system collapsed, leading to the end of communism in the satellite countries in 1989, and the dissolution of the Soviet Union itself in 1991. As a consequence, Europe's integration deepened, the continent became depolarised, and the European Union expanded to subsequently include many of the formerly communist European countries – Romania and Bulgaria (2007) and Croatia (2013).

paragraph_text: After his release, Rodoljub Čolaković emigrated to the Soviet Union and later took part in the Spanish Civil War on the Republican side.

paragraph_text: After the Russian Revolution and the Russian Civil War the ships of the fleet became dispersed over various countries, and Soviet Russia made efforts via international courts to have them returned. Dobroflot was restored in the Soviet Union in 1922 and included into the Sovtorgflot ("Soviet Commercial Fleet") in 1925.

paragraph_text: As African states became independent in the 1960s, the Soviet Union offered many of their citizens the chance to study in Russia. Over a period of 40 years, about 400,000 African students from various countries moved to Russia to pursue higher studies, including many Black Africans. This extended beyond the Soviet Union to many countries of the Eastern bloc.

paragraph_text: Pechora Radar Station () is an early warning radar near Pechora in the Komi Republic, northern Russia. It is a key part of the Russian early warning system against missile attack and was built by the Soviet Union, becoming operational in 1984. It is run by the Russian Aerospace Defence Forces.

paragraph_text: For its part, the Soviet Union harbored fears of invasion. Having suffered at least 27 million casualties during World War II after being invaded by Nazi Germany in 1941, the Soviet Union was wary of its former ally, the United States, which until late 1949 was the sole possessor of atomic weapons. The United States had used these weapons operationally during World War II, and it could use them again against the Soviet Union, laying waste its cities and military centers. Since the Americans had a much larger air force than the Soviet Union, and the United States maintained advance air bases near Soviet territory, in 1947 Stalin ordered the development of intercontinental ballistic missiles (ICBMs) in order to counter the perceived American threat.

paragraph_text: Militarization was another aspect of the Soviet state. Large parts of the country, especially the coastal areas, were closed to all but the Soviet military. Most of the sea shore and all sea islands (including Saaremaa and Hiiumaa) were declared "border zones". People not actually residing there were restricted from travelling to them without a permit. A notable closed military installation was the city of Paldiski, which was entirely closed to all public access. The city had a support base for the Soviet Baltic Fleet's submarines and several large military bases, including a nuclear submarine training centre complete with a full-scale model of a nuclear submarine with working nuclear reactors. The Paldiski reactors building passed into Estonian control in 1994 after the last Russian troops left the country. Immigration was another effect of Soviet occupation. Hundreds of thousands of migrants were relocated to Estonia from other parts of the Soviet Union to assist industrialisation and militarisation, contributing an increase of about half a million people within 45 years.

paragraph_text: Nikita Sergeyevich Khrushchev (15 April (O.S. 3 April) 1894 -- 11 September 1971) was a Soviet politician who led the Soviet Union during part of the Cold War as the First Secretary of the Communist Party of the Soviet Union from 1953 to 1964, and as Chairman of the Council of Ministers, or Premier, from 1958 to 1964. Khrushchev was responsible for the de-Stalinization of the Soviet Union, for backing the progress of the early Soviet space program, and for several relatively liberal reforms in areas of domestic policy. Khrushchev's party colleagues removed him from power in 1964, replacing him with Leonid Brezhnev as First Secretary and Alexei Kosygin as Premier.

paragraph_text: Armenia was annexed by Bolshevist Russia and along with Georgia and Azerbaijan, it was incorporated into the Soviet Union as part of the Transcaucasian SFSR (TSFSR) on 4 March 1922. With this annexation, the Treaty of Alexandropol was superseded by the Turkish-Soviet Treaty of Kars. In the agreement, Turkey allowed the Soviet Union to assume control over Adjara with the port city of Batumi in return for sovereignty over the cities of Kars, Ardahan, and Iğdır, all of which were part of Russian Armenia.

paragraph_text: After World War II, eastern European countries such as the Soviet Union, Poland, Czechoslovakia, Hungary, Romania and Yugoslavia expelled the Germans from their territories. Many of those had inhabited these lands for centuries, developing a unique culture. Germans were also forced to leave the former eastern territories of Germany, which were annexed by Poland (Silesia, Pomerania, parts of Brandenburg and southern part of East Prussia) and the Soviet Union (northern part of East Prussia). Between 12 and 16,5 million ethnic Germans and German citizens were expelled westwards to allied-occupied Germany.

paragraph_text: Following the Welles Declaration of July 23, 1940, the annexation of Latvia into the Soviet Union (USSR) on 5 August 1940 was not recognized as legitimate by the United States, the European Community, and recognition of it as the nominal fifteenth constituent republic of the USSR was withheld for five decades. Its territory was subsequently conquered by Nazi Germany in June -- July 1941, before being retaken by the Soviets in 1944 -- 1945. Nevertheless, Latvia continued to exist as a de jure independent country with a number of countries continued to recognize Latvian diplomats and consuls who still functioned in the name of their former governments.

paragraph_text: The most extreme case was the Soviet Union, and this model may still be followed in some countries: it was a separate service, on a par with the navy or ground force. In the Soviet Union this was called Voyska PVO, and had both fighter aircraft and ground-based systems. This was divided into two arms, PVO Strany, the Strategic Air defence Service responsible for Air Defence of the Homeland, created in 1941 and becoming an independent service in 1954, and PVO SV, Air Defence of the Ground Forces. Subsequently these became part of the air force and ground forces respectively

Question: When did the country Dagda is located become part of the Soviet Union?
Answer: 5 August 1940