Polish Diaspora abroad counts 15-20 mln people. Poles belong to the nationalities that have relatively high fraction of emigrants compared to the number of Poles that live in Poland (about 40 mln now, read more about it in the article: Poland - Basic Information - Facts - Statistics ). This is due to difficult Polish history, loss of independence, economical problems and due to the communism. The total numbers of Poles abroad are given in the article Polish Diaspora (Polonia) Worldwide .
We have to remember that the Poles abroad are not necessarily the immigrants. For instance the Poles who remained in the Soviet Union, sometimes against their will, sometimes because their house and their family were settled there for hundreds of years. They ended up to live in a different country after the war when the boarders were changed as a result of Jalta treaty. So, these people form a Polish minority or Poles living abroad but not the immigrants.
The Main Waves of Emigration from Poland
The first wave of tens of thousands of political emigrants left Poland in the result of the loss of independence at the end of XVIII century and after unsuccessful national uprisings of 1830 and 1863. Many of them contributed to the freedom of other countries - like general Pulaski and Kosciuszko in the USA or general Bem in Hungary. The most prominent Polish poets and our national spiritual leaders, Adam Mickiewicz and Juliusz Slowacki created their best work while abroad. The most important wave of emigrants left Poland after the uprising in 1830 and this emigration is usually called GREAT EMIGRATION (wielka emigracja) since many great generals, politicians, writers, national heroes have to leave Poland to avoid imprisonment, death or sending to Siberia.
The second wave - about 3.5 millions people left Polish territories that belong to Austria, Russia and Prussia in years 1870-1913. This was mainly economical immigration, so called "for bread" (za chlebem) immigrants. This immigration consisted mainly of peasants from economically neglected rural provinces, many from the mountainous region of Galicia (Southeastern Poland) that belonged to Austria, but not only. People from all the divided Polish land were immigrating and they are difficult to account for as Poles since they were the citizens of Russia, Prussia and Austria. Also many Jews left in that time. Jewish people were more determined to stay in the new country, whereas some Poles left only temporarily and then came back. The majority of these people left Poland to the USA, the others to Germany, France or Belgium.
The third wave took place during the twenty years of independence between World War I and World War II when 2.5 million Poles left for the search of a better job or future. Altogether in years 1870 - 1938 over 6 millions people left Poland.
During World War II - 3 million Poles ended up beyond Polish boarders, mainly as the soldiers who fought against the Hitler regime in foreign armies or in Polish armies formed abroad. The Soviet Union Stalin's regime sent to Siberia and Kazakchstan at least 1 mln 700 thousands of Polish citizens during the two years when they occupied Eastern part of Poland and before Nazi Germany attacked them. Some of the Poles were saved thanks to enrolling to general Anders army (over 100 thousands) later on. In the effect of the agreement with Soviet Union about 300,000 Poles returned to Poland from the Soviet-occupied territories after the war. The rest was either killed, died on starvation or in the labor camps or remained in the Soviet Union since the boarders changed in the course of Jalta treaty and Poland lost 1/3 of its territory on the East. About 800 thousands of Polish citizens remained in Western Europe after World War II. Among them were soldiers and generals, labor camp prisoners or people who were involved in fight against Hitler on behalf of the Home Army (Armia Krajowa) - and they could not come back to Poland after the war because of the danger of Soviet persecutions. Also many politicians, scientists and artists who did not foresee their chance in the communistic of Soviet-type run Poland. After the World War II the center of Polish immigrant political life abroad was England with the Polish Government in Exile which ceased to exist with the fall of communism in 1990.
Travel abroad was restricted to Poles until 1980, still over a million people left Poland permanently in that time: about 600 thousands in years 1945- 1955 and the next 800 thousands in years 1956-1979. More people left after 1956 not because the life became more difficult (this was the time when Stalin-type of regime ceased to exist and the thick wall became a bit thinner and more transparent) but rather because it was easier to receive the passport and to leave abroad. Some of this emigration was legal - for instance in the action of uniting families (akcja laczenia rodzin) between Poland and Germany. Between 1950 and 1987, about 850 thousands of people immigrated to Germany in the effect of this action as resettlers ("aussiedlers" in German). Many of these people claimed German connections. But the truth is that quite a lot of this emigration was mainly from economical reasons.
In the years 1967-1968 the exodus of Polish Jews (about 20 thousands) took place. It was caused partly by internal tensions in Polish communist party, between so called patriots and nationalists and the internationalists, some of the communists of the second group were of Jewish origin. It was also magnified by students riots of March 1968 and by the international situation in Israel.
The next big wave of immigration took place in years 1980-1990 when about 100 thousands people was leaving Poland every year. This immigration was mainly economical (so called "emigracja dorobkowa"), although some Solidarity activists have to leave after martial law was enforced. Majority of people who left were young and good educated people who did not foresee political or economical change. Majority of people left to Germany, Austria, or through the temporary camps in Italy to Canada, Australia or the USA.
Some sociologists predict that another immigration wave started with the day when Poland joined the EU on May 1st 2004. Some EU countries allowed the new EU members to apply for a job with the day they joined EU. Among these countries is Great Britain, Ireland and Sweden. But this emigration has more temporary character and it is related to the prospects of Poles to find a legal and a good paid job abroad. For the last ten years the unemployment in Poland was between 14-20%, according to the numbers in the article Unemployment in Poland - in Figures - Statistics . Read also more articles about Polish economical situation and the reasons of unemployment in the series of articles on economy.
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If you are trying to find your Polish roots you need to buy this book written by Rosemary A. Chorzempa, entitled: Polish Roots