O futuro da Europa foi decidido na Conferência de Teerão há 75 anos

The "Big Three" at the Tehran Conference
Left to right: Joseph Stalin, Franklin D. Roosevelt and Winston Churchill

  
The Tehran Conference (codenamed Eureka) was a strategy meeting held between Joseph Stalin, Franklin D. Roosevelt, and Winston Churchill from 28 November to 1 December 1943. It was held in the Soviet Embassy in Tehran, Iran and was the first of the World War II conferences held between all of the "Big Three" Allied leaders (the Soviet Union, the United States, and the United Kingdom). It closely followed the Cairo Conference and preceded both the Yalta and Potsdam Conferences. Although all three of the leaders present arrived with differing objectives, the main outcome of the Tehran Conference was the commitment to the opening of a second front against Nazi Germany by the Western Allies. The conference also addressed relations between the Allies and Turkey and Iran, operations in Yugoslavia and against Japan as well as the envisaged post-war settlement. A separate protocol signed at the conference pledged the Big Three's recognition of Iran's independence.
 
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Stalin dominated the conference, using the Soviet victory at the Battle of Kursk and military might, as well as key positions on the German front, to get his way. Roosevelt attempted to cope with Stalin's onslaught of demands, but was able to do little except appease Stalin. Churchill mostly argued for his Mediterranean plan instead of Operation Overlord, to the annoyance of diplomats and officials. These weaknesses and divisions played into Stalin's hands.
One of Roosevelt and Churchill's main concessions concerned post-war Poland. Stalin wished for an area in the eastern part of Poland to be added to the Soviet Union, and for the border to be lengthened elsewhere in the country. Roosevelt and Churchill agreed to this demand, and Poland's borders were declared to lie along the Oder and Neisse rivers and the Curzon line, despite protests of the Polish government-in-exile in London. Churchill and Roosevelt also consented to the Soviet Union setting up puppet communist governments in Poland, Czechoslovakia, the Baltic States, Romania, and other Eastern European countries which would result in a loss of freedom by these countries for the next fifty years and would be the genesis of the Cold War. After the conference it was agreed that military leaders of the three countries would meet together often, for further discussion.
One remarkable thing that was also decided at the Tehran Conference was the way in which the Allies would deal with Finland, a free democratic country which cooperated with Germany after Soviet aggression and one that had not signed the Tripartite Pact, and had not declared war on any free Allied countries. Their decision stipulated that Finland could negotiate its own peace treaty with the Soviet Union rather than being subject to the unconditional surrender that faced the Germans and Japanese.   

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