I have met those people too, they are not only in the US
1) the Baltic refugees are a special case. A lot of them fought on the German side because they thought it was the only way to keep their countries free. Some of them, specially in Lithuania were involved in the cleansing of the Jews. All this is very well documented. When the Russians arrived they took they boats and flew to Sweden. I know plenty or personal stories too. After the Russian take over nobody flew to the West. There was a special case in the 80s when a sailor took advantage of a storm and since the boat had to take refuge into Swedish territorial waters, he swam to liberty. He was shot at by the captain, wich triggered a diplomatic incident.
2) Yugoslavia is a special case. As I told you tenth of thousands of Yougoslavs worked abroad and then stayed perfectly legally. I had plenty of Yugoslavian friends in Sweden and they used to go back home on vacations - UNDER TITO. You didn't even need a visa to go there if you were French or Swedish. Besides the regimes that came into place after Tito in those non serb republics weren't much better. Remember to that specially the Croatians sided with the Nazis during WWII.
4) My point is that the MAJORITY of refugees must have come BEFORE the falling of the Iron curtain. If there was a wall built in Eastern Germany it was because the country was bleeding. I don't remind any similar situation in other eastern countries, maybe with some exceptions during the Hungarian and Czeckoslovakian episodes. That doesn't mean either that several thousands didn't make it out during the Iron curtain period
I have no reason to doubt the veracity of the stories of your friends.
facts :
Between the end of World War II and the erection of the Berlin Wall in 1961, more than 3,700,000 refugees from East Germany travelled to West Germany for asylum from the Soviet occupation. (Wikipedia)
from encyclopedia britannica :
Meanwhile a United Nations Relief and Rehabilitation Administration (UNRRA) had been created in 1943. UNRRA was succeeded by the International Refugee Organisation, established in 1946; and that in turn gave way to the United Nations High Commission for Refugees in 1950. All these bodies, however, were plagued by political conflict, in particular the outbreak of the Cold War.
UNRRA was limited under its Articles of Agreement to assisting in the 'repatriation or return' to their home countries of 'displaced persons'. It transported millions of former concentration-camp dwellers, forced labourers and other victims of the Nazis to countries such as France, Belgium, and Greece.
Over two million Soviet citizens were returned by the western Allies to areas under Soviet control. They were moved in batches, generally in return for equivalent numbers of citizens of western countries, an equivalence insisted upon by the Soviet authorities.
Many of the Soviets departed willingly. But others did not, and their forcible return conflicted with the 'non-refoulement' principle. Many citizens of east European states that were taken over by Communists also resisted repatriation. Most sought refuge in western Europe, the United States, Canada, or Australia.
Cold War considerations, combined with calculation of labour requirements in industries such as mining, led Britain, Australia and other countries to grant Poles and some others permanent settlement. The creation of the State of Israel in 1948 finally provided a secure refuge for Jews who had been hounded from their homes in central and eastern Europe. But the buoyant United States economy held out the most tantalising hope to refugees.
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The deepening of east-west conflict in the early years of the Cold War provided the context for subsequent US legislation. The Refugee Relief Act of 1953 provided for the admission over three years of 214,000 refugees - of these, it was laid down that 186,000 should be from Communist countries.
By 1959 some 900,000 European refugees had been absorbed by west European countries. In addition, 461,000 had been accepted by the USA, and a further 523,000 by other countries. But many 'hard-core' refugees still remained in camps. At that point the United Nations launched an ambitious effort to resolve the refugee problem once and for all.
World Refugee Year, in 1959-1960, was designed as a 'clear the camps' drive. It achieved some significant results - at any rate in Europe. By the end of 1960, for the first time since before World War Two, all the refugee camps of Europe were closed.
http://www.bbc.co.uk/history/war/wwtwo/refugees_06.shtml