How Estonia lost its independce to the Soviet Union in 1940

Declaration of neutrality

Estonia, Latvia and Lithuania jointly declared their neutrality on November 18, 1938, in Riga, at the Conference of Baltic Foreign Ministers with their respective parliaments passing neutrality laws later that year. Estonia passed a law ratifying its neutrality on December 1st, 1938, which was modelled on Sweden's declaration of neutrality of May 29, 1938.Also importantly, Estonia had asserted its neutrality in its very first constitution, as well as the Treaty of Tartu concluded in 1920 between Republic of Estonia and the Russian SFSR.

Molotov–Ribbentrop Pact

Planned and actual divisions of Europe, according to the Molotov–Ribbentrop Pact, with later adjustments Molotov–Ribbentrop Pact
Early in the morning of August 24, 1939, the Soviet Union and Nazi Germany signed a 10-year non-aggression pact, called the Molotov–Ribbentrop pact. Most notably, the pact contained a secret protocol, revealed only after Germany's defeat in 1945, according to which the states of Northern and Eastern Europe were divided into German and Soviet "spheres of influence".In the north, Finland, Estonia and Latvia were assigned to the Soviet sphere Poland was to be partitioned in the event of its "political rearrangement"—the areas east of the Narev, Vistula and San Rivers going to the Soviet Union while Germany would occupy the west.[10] Lithuania, adjacent to East Prussia, would be in the German sphere of influence, although a second secret protocol agreed in September 1939 assigned the majority of Lithuania to the USSR.

The beginning of World War II

World War II began with the invasion of an important regional ally of Estonia – Poland, by Germany. Although some coordination existed between Germany and the USSR early in the war,the Soviet Union communicated to Nazi Germany its decision to launch its own invasion seventeen days after Germany's invasion, as a result, in part, of the unforeseen rapidity of the Polish military collapse.
On September 24, 1939, with the fall of Poland to Nazi Germany and the USSR imminent and in light of the Orzeł incident, the Moscow press and radio started violently attacking Estonia as "hostile" to the Soviet Union. Warships of the Red Navy appeared off Estonian ports, and Soviet bombers began a threatening patrol over Tallinn and the nearby countryside.
Moscow demanded that Estonia allow the USSR to establish military bases and station 25,000 troops on Estonian soil for the duration of the European war.[18] The government of Estonia accepted the ultimatum signing the corresponding agreement on September 28, 1939.

The pact was made for ten years:

Estonia granted the USSR the right to maintain naval bases and airfields protected by Red Army troops on the strategic islands dominating Tallinn, the Gulf of Finland and the Gulf of Riga;
The Soviet Union agreed to increase her annual trade turnover with Estonia and to give Estonia facilities in case the Baltic is closed to her goods for trading with the outside world via Soviet ports on the Black Sea and White Sea;
The USSR and Estonia undertook to defend each other from "aggression arising on the part of any great European power";
It was declared: the pact "should not affect" the "economic systems and state organizations" of the USSR and Estonia
There is no consensus in Estonian society about the decisions that the leadership of the Republic of Estonia made at that time.

When Soviet troops marched into Estonia the guns of both nations gave mutual salutes, and bands played both the Estonian anthem and the Internationale, the anthem of the USSR, at the time.

Similar demands were forwarded to Finland, Latvia and Lithuania. Finland resisted, and was attacked by the Soviet Union on November 30. Because the attack was judged as illegal, the Soviet Union was expelled from the League of Nations on December 14 Finland held out in the Winter War until March 1940, when the Moscow Peace Treaty was signed.

The first population loss for Estonia was the repatriation of about 12,000–18,000 Baltic Germans to Germany.
In the summer of 1940 the occupation of Estonia was carried through as a regular military operation. 160,000 men, supported by 600 tanks were concentrated for the invasion into Estonia. 5 divisions of the Soviet Air Force with 1150 aircraft blockaded the whole Baltic air space against Estonia, Lithuania and Latvia. The Soviet Baltic Fleet blockaded the operation from the sea. The Soviet NKVD was ordered to be ready for the reception of 58,000 prisoners of war.[3]

Soviet occupation.

On June 3, 1940, all Soviet military forces based in the Baltic states were concentrated under the command of Aleksandr Loktionov.[24]

On June 9, the directive 02622ss/ov was given to the Red Army's Leningrad Military District by Semyon Timoshenko to be ready by June 12 to (a) Capture the vessels of the Estonian, Latvian and Lithuanian Navy in their bases and/or at sea; (b) Capture the Estonian and Latvian commercial fleet and all other vessels; (c) Prepare for an invasion and landing in Tallinn and Paldiski; (d) Close the Gulf of Riga and blockade the coasts of Estonia and Latvia in Gulf of Finland and Baltic Sea; (e) Prevent an evacuation of the Estonian and Latvian governments, military forces and assets; (f) Provide naval support for an invasion towards Rakvere; (g) Prevent Estonian and Latvian airplanes from flying either to Finland or Sweden.

Soviet terror

The Soviet authorities, having gained control over Estonia, moved rapidly to stamp out any potential opposition to their rule. During the first year of Soviet occupation (1940–1941) over 8,000 people, including most of the country's leading politicians and military officers, were arrested. About 2,200 of the arrested were executed in Estonia, while most others were moved to prison camps in Russia, from where very few were later able to return alive. On July 19, 1940, the Commander-in-chief of the Estonian Army Johan Laidoner was captured by the NKVD and deported together with his spouse to the town of Penza. Laidoner died in the Vladimir Prison Camp, Russia on March 13, 1953. President of Estonia, Konstantin Päts was arrested and deported by the Soviets to Ufa in Russia on July 30; he died in a psychiatric hospital in Kalinin (currently Tver) in Russia in 1956. 800 Estonian officers, i.e., about a half of the total were executed, arrested or starved to death in prison camps.

Mass deportation was another key weapon of Soviet control. In spring 1941 the Serov Instructions "On the Procedure for carrying out the Deportation of Anti-Soviet Elements from Lithuania, Latvia, and Estonia" was issued, providing procedure for the deportation of those deemed to be 'anti-Soviet'. This order was operationalised on June 14, 1941, when the mass June deportation took place simultaneously in all three Baltic countries; almost 10,000 Estonians[46] were deported in just a couple of days.[nb 2][48] Forcible conscription into the Red Army began after the German invasion of the Soviet Union on June 22, 1941, but the Estonian conscripts were soon deemed unreliable and assigned to "labour battalions". Of the 33,000 Estonian conscripts, more than 10,000 died in these inhuman conditions due to disease, hunger and cold.[49]

When Estonia was proclaimed as a Soviet Republic, the crews of 42 Estonian ships in foreign waters refused to return to their homeland (about 40% of the pre-war Estonian fleet). These ships were requisitioned by the British powers and were used in Atlantic convoys. During the time of the war, approximately 1000 Estonian seamen served in the British militarised merchant marine, 200 of them as officers. A small number of Estonians served in the Royal Air Force, in the British Army and in the US Army, altogether no more than two hundred.