The Estonian Soviet Socialist Republic (Estonian SSR), Soviet Estonia, or simply Estonia, was a union republic of the Soviet Union (USSR), covering the occupied and annexed territory of Estonia in 1940–1941 and 1944–1991. The Estonian SSR was nominally established to replace the until then independent Republic of Estonia on 21 July 1940, a month after the 16–17 June 1940 Soviet military invasion and occupation of the country during World War II. After the installation of a Stalinist government which, backed by the occupying Soviet Red Army, declared Estonia a Soviet constituency, the Estonian SSR was subsequently incorporated into the Soviet Union as a "union republic" on 6 August 1940. Estonia was occupied by Nazi Germany in 1941, and administered as a part of Reichskommissariat Ostland until it was reconquered by the USSR in 1944.
The majority of the world's countries did not recognise the incorporation of Estonia into the Soviet Union de jure and only recognised its Soviet administration de facto or not at all. A number of countries continued to recognise Estonian diplomats and consuls who still functioned in the name of their former government. This policy of non-recognition gave rise to the principle of legal continuity, which held that de jure, Estonia remained an independent state under occupation throughout the period 1940–1991.
On 16 November 1988, Estonia became the first of the then Soviet-controlled countries to declare state sovereignty from the central government in Moscow. On 30 March 1990, the newly elected parliament declared that the Republic of Estonia had been illegally occupied since 1940, and formally announced a transitional period for the restoration of the country's full independence. Subsequently, on 8 May 1990, the use of all Soviet symbols in Estonia was officially abolished and from the "Estonian Soviet Socialist Republic" two words, "Soviet" and "Socialist", were dropped, effectively returning to the name "Republic of Estonia". The parliament of Estonia declared the re-establishment of full independence on 20 August 1991. The Soviet Union formally recognised the independence of Estonia on 6 September 1991.
History
Second World War
The Nazi-Soviet Pact which was signed on 23 August 1939, a week before the outbreak of World War II, secretly assigned Estonia to the Soviet "sphere of influence". On 24 September 1939, warships of the Soviet Navy blocked the major ports of Estonia, a neutral country, and Soviet bombers began patrolling over and around its capital city Tallinn. Moscow demanded that Estonia allow the USSR to establish Soviet military bases on its territory and station 25,000 troops in these bases "for the duration of the European war". The government of Estonia yielded to the ultimatum, signing the corresponding mutual assistance agreement on 28 September 1939.
Soviet occupation of Estonia
On 12 June 1940, the order for total military blockade of Estonia was given to the Soviet Soviet Baltic fleet. On 14 June, the Soviet military blockade of Estonia went into effect while the world's attention was focused on the fall of Paris to Nazi Germany. Two Soviet bombers shot down a Finnish passenger aircraft "Kaleva" flying from Tallinn to Helsinki carrying three diplomatic pouches from the U.S. legations in Tallinn, Riga and Helsinki. On 16 June, Soviet NKVD troops raided border posts in Estonia (along with Lithuania and Latvia). Soviet leader Joseph Stalin claimed that the 1939 mutual assistance treaties had been violated, and gave six-hour ultimatums for new governments to be formed in each country, including lists of persons for cabinet posts provided by the Kremlin. The Estonian government decided, in accordance with the Kellogg–Briand Pact, to not respond to the ultimatums by military means. Given the overwhelming Soviet force both on the borders and inside the country, the order was given not to resist in order to avoid bloodshed and open war.