The Republic of Poland is located in Eastern Europe, which includes other Visegrad states - Czechia, Slovakia and Hungary, along with Baltic States (Lithuania, Latvia and Estonia) and the Republic of Belarus.
Eastern Europe is also one of the most linguistically and religiously diverse regions in the world, where at the same time, all the cultures preserve strong common socio-historical bonds. Eastern European populations speak Slavic, Baltic and Finno-Ugric groups of languages, and practice Roman and Greek Catholicisms, Protestantism and Christian Orthodox, with heavy influence of local traditional customs.
FORMATION OF THE POLISH STATE, AN EMERGENCE and DECLINE OF RECHPOSPOLITA, and RESTORATION OF INDEPENDENCE
The first Western Slavic civilization is considered to be the state of Samo or Moravia, founded by Dukes Mojmir I and Rastislav I, in approximately 9th Century A.D. The Moravian state was converted to Christianity (of Orthodox stock) by Duke Rastislav I, after establishing ties with prominent Roman (Byzantine) Missionaries and Slavic linguists, Saints Cyril and Methodius, around 863 A.D. The Moravian Empire included modern-day Hungary, Czechia, Slovakia and southern Poland (Silesia).
Poland was formed as a sovereign state after the adoption of Christianity (of Catholic stock) by Duke Mieszko I in 966 A.D. In 1025, Boheslav I the Brave was proclaimed as the first King of Poland. In the following centuries, Poland was expanding trade, social and cultural ties with other states, particularly with Lithuanian(-Belarusian) Princedom. In 1386, Polish Queen Jadwiga succeeded to baptize pagan Lithuanian Empire to Roman Catholic state, as well to expand the sphere of influence of Polish aristocracy on Lithuanian-Belorussian nobility, after marrying Lithuanian Prince Yagailo I.
On July 1st 1569, the Lublin Treaty officially merged Lithuanian-Belorussian Princedom and Kingdom of Poland into Rzeczpospolita or the Polish-Lithuanian Commonwealth. On October 19th 1596, the Union of Brest united population practicing Orthodox and Roman Catholic stocks of Christianity in Russian-speaking Belarus region. Thus, significant portion of Belarusian population practice Greek Catholicism - Christians who follow Orthodox beliefs but recognize a Roman Pope as the head of the Church.
Polish-Lithuanian Commonwealth included modern-day Poland, Lithuania, Latvia, Belarus, part of Russia and most of Estonia and Ukraine, before facing long-term and rapid decline. Rzeczpospolita ceased to exist after the Third Partition Treaty in 1795, which divided Polish territories between Austria, Russia and Prussia.
In 1807, French Emperor Napoleon I recognized conquered Polish lands as semi-independent Duchy of Warsaw. Nevertheless, in 1815, Russia ceded the French Protectorate and Russian Emperor Alexander I proclaimed himself as the King of Poland. The last sovereign Polish-speaking state, the Krakow's Republic, was annexed by the Austrian Empire in 1846.
The ultimate independence and restoration of Republic was achieved after Russian Revolution on November 7th 1917 and at the end of World War I on November 11th 1918, under the guidance of General Josef Pilsudski.
Between 1939 and 1945, Poland was occupied by Nazi Germany, which racist policies brought to massive extermination of Polish citizens of Slavic and Jewish descents.
THE SOVIET ERA and THE COLLAPSE OF THE SOVIET BLOC
After the end of World War II, the Visegrad and the Baltic states faced several decades of Communist oppression that abused freedom, democracy and free enterprises. Nevertheless, the dissident movements, such as Forest Brothers rebellions (1945-1956) in Baltic states, Hungarian uprising (1956), purge in Czechoslovakia (1968) and range of Polish protests (1968), honourably resisted Soviet regimes.
At the end of Cold War era in 1989, after several decades of economic and social stagnation, Visegrad and Baltic states eventually achieved peaceful transition to free market and democracy. On February 15th 1991, Czechoslovakia, Poland and Hungary signed the Visegrad treaty, which marks the beginning of political and cultural alliance, and marked the end of Communist chapter in those three (later four) nation-states.
1989 and BEYOND
The Visegrad and the Baltic states became members of the European Union in 2004 and the NATO military alliance between 1999 and 2004, and eventually joined the Schengen area in 2007.
In recent years, Polish enterprises contribute investments for less-developing economies across Eastern European region, impacted by EU sanctions against Russia, since February 2014 . In parallel, Eastern European states provide NATO military trainings and protection from all forms of potential foreign threats to national sovereignty and democracy .
Amid the ongoing migration crisis, commenced in 2015, the Visegrad states with Belarus and Baltic nations, co-operate in terms of solving migration crisis across the EU, by developing a new long-term strategy of humanitarian support and social stability for the countries fled by refugees .
History of Poland and Eastern Europe | By Konstantin K. Manyakin, CPCC Intern
European Studies Graduate (EURUS Program), Carleton University & Young European Federalists (JEF) member
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 Janjevic, D. (2016), “Visegrad leaders: Merkel meets European critics of her refugee policies”. Deutsche Welle, 26 August. Retrieved from: http://www.dw.com/en/visegrad-leaders-merkel-meets-european-critics-of-her-refugee-policies/a-19504957