headquarters_location communist party of western belarus
The Communist Party of Western ___MASK11___ ( Polish : Komunistyczna Partia Zachodniej Biaorusi , KPZB ; Belarusian :     ,  ) was a banned Belarusian political party in the Interwar ___MASK32___ infiltrated by Soviet special services ( similar to German fifth column ) operating in the territory of present - day West ___MASK11___ from 1923 until 1939 ; in Polesie ( 1932 -- 1933 ) and in Sonim county ( 1934 ) . The organization was stockpiling smuggled weapons years before the 1939 Soviet invasion of ___MASK32___ and received Russian instructions about how to act afterwards . The Soviet invasion of ___MASK32___ was a Soviet military operation that started without a formal declaration of war on 17 September 1939 . On that morning , 16 days after Nazi Germany invaded ___MASK32___ from the west , the Soviet Union invaded ___MASK32___ from the east . The invasion and battle lasted for the following 20 days and ended on 6 October 1939 with the two - way division and annexation of the entire territory of the ___MASK4___ by both Germany and the Soviet Union . The joint German - Soviet invasion of ___MASK32___ was secretly agreed in the Molotov - Ribbentrop Pact , signed on 23 August 1939 . Byelorussia , officially the Byelorussian Soviet Socialist Republic ( Byelorussian SSR or BSSR " Bielaruskaja Savieckaja Sacyjalistynaja Respublika / Bielaruskaja SSR ", " Belorusskaja Sovetskaja Socialistieskaja Respublika , Belorusskaja SSR "), also referred to as Soviet Byelorussia was a sovereign state from between 1920 - 1922 and 1991 - 1994 , one of fifteen constituent republics of the Soviet Union ( USSR ) existed from 1922 - 1991 , and a sovereign part with its own legislation from 1990 to 1991 . To the west it bordered ___MASK32___ . Within the Soviet Union , it bordered ___MASK37___ and Latvian to the north , the Russian SFSR to the east and Ukraine to the south . The Invasion of ___MASK32___ , also known as the September Campaign , or the 1939 Defensive War in ___MASK32___ ( or " Wojna obronna 1939 roku "), and alternatively the ___MASK32___ Campaign or " Fall Weiss " in Germany ( Case White ), was a joint invasion of ___MASK32___ by Nazi Germany , the Free City of Danzig , the Soviet Union , and a small Slovak contingent , that marked the beginning of World War II in Europe . The German invasion began on 1 September 1939 , one week after the signing of the Molotov  Ribbentrop Pact , while the Soviet invasion commenced on 17 September following the Molotov - Tg agreement that terminated the Russian and Japanese hostilities in the east on 16 September . The campaign ended on 6 October with Germany and the Soviet Union dividing and annexing the whole of ___MASK32___ under the terms of the German - Soviet Frontier Treaty . Nazi ___MASK39___ is the common English name for the period in German history from 1933 to 1945 , when ___MASK39___ was governed by a dictatorship under the control of Adolf Hitler and the Nazi Party ( NSDAP ). Under Hitler ' s rule , ___MASK39___ was transformed into a fascist state in which the Nazi Party took totalitarian control over nearly all aspects of life . The official name of the state was " Deutsches Reich " from 1933 to 1943 and " Großdeutsches Reich " (" Greater German Reich ") from 1943 to 1945 . The period is also known under the names the Third Reich and the National Socialist Period ( abbreviated as " NS - Zeit "). The Nazi regime came to an end after the Allied Powers defeated ___MASK39___ in May 1945 , ending World War II in Europe . The ___MASK4___ , also known as the Second Commonwealth of Poland or interwar Poland , refers to the country of Poland between the First and Second World Wars ( 1918  1939 ). Officially known as the Republic of Poland or the Commonwealth of Poland , the Polish state was recreated in 1918 , in the aftermath of World War I . When , after several regional conflicts , the borders of the state were fixed in 1922 , Poland ' s neighbours were Czechoslovakia , Germany , the Free City of Danzig , Lithuania , Latvia , Romania and the Soviet Union . It had access to the Baltic Sea via a short strip of coastline either side of the city of Gdynia . Between March and August 1939 , Poland also shared a border with the then - Hungarian governorate of Subcarpathia . Despite internal and external pressures , it continued to exist until 1939 , when Poland was invaded by Nazi Germany , the Soviet Union and the Slovak Republic , marking the beginning of World War II in Europe . The Second Republic was significantly different in territory to the current Polish state . It included substantially more territory in the east and less in the west . ___MASK21___ (, , " Byalistok ") is the largest city in northeastern ___MASK32___ and the capital of the Podlaskie Voivodeship . The Soviet Union , officially the Union of Soviet Socialist Republics ( USSR " ) was a socialist state in Eurasia that existed from 1922 to 1991 . A union of multiple subnational republics , its government and economy were highly centralized . The Soviet Union was a one - party federation , governed by the Communist Party with ___MASK3___ as its capital . In the context of the history of the 20th century , the interwar period or " interbellum " ( Latin : " inter -", " between " + " bellum ", " war ") was the period between the end of the First World War ( 1914  18 ) and the beginning of the Second World War ( 1939  45 ) the period beginning with the Armistice of 11 November 1918 that concluded the First World War and the ensuing ___MASK81___ Peace Conference in 1919 , and ending in September 1939 with the German invasion of ___MASK32___ and the start of the World War II . Kresy Wschodnie or Kresy ( Eastern Borderlands , or Borderlands ) was a historical region of the ___MASK4___ during the interwar period constituting nearly half of the territory of the state ; where the ethnic Poles , being the largest group , were roughly equal in their number to the size of the national minorities ( with notable exceptions ). Administratively , the territory of Kresy was composed of voivodeships of Lwów , Nowogródek , Polesie , Stanisawów , Tarnopol , Wilno , Woy , and the Biaystok . Today , these territories are divided between Western Ukraine , Western Belarus , and south - eastern Lithuania , with such major cities as Lviv , Vilnius , and Hrodna no longer in Poland . In the ___MASK4___ the term " Kresy " roughly equated with the lands beyond the so - called Curzon Line , which was suggested after World War I in December 1919 by the British Foreign Office as the eastern border of the re - emerging sovereign Republic following the century of partitions . In September 1939 , after the Soviet Union joined Nazi Germany in their attack on Poland in accordance with the Molotov  Ribbentrop Pact , the territories were incorporated into Soviet Ukraine , Belarus and Lithuania in the atmosphere of terror . ___MASK11___ ( lat . ',      ), officially the Republic of ___MASK11___ , formerly known by its Russian name Byelorussia ( though this name is no longer used in ___MASK11___ itself , even in Russian language ), is a landlocked country in Eastern Europe bordered by Russia to the northeast , ___MASK27___ to the south , ___MASK32___ to the west , and ___MASK37___ and Latvia to the northwest . Its capital and most populous city is Minsk . Over 40 % of its is forested . Its strongest economic sectors are service industries and manufacturing . Until the 20th century , different states at various times controlled the lands of modern - day ___MASK11___ , including the Principality of Polotsk ( 11th to 14th centuries ), the Grand Duchy of ___MASK37___ , the Polish  Lithuanian Commonwealth , and the Russian Empire . West ___MASK11___ ( Zakhodnyaya ___MASK11___ ) is a historical region of modern - day ___MASK11___ ; comprising the territory which belonged to the ___MASK4___ during the interwar period in accordance with the international peace treaties . It used to form the northern half of the Polish " Kresy Wschodnie " macroregion before the 1939 Nazi - Soviet invasion of Poland ( the Eastern Borderlands ). Following the end of World War II in Europe the territory of West ___MASK11___ was ceded to the USSR by the Allied Powers , while the city of Biaystok with surroundings was returned to Poland . Until the dissolution of the Soviet Union in 1991 West ___MASK11___ formed a significant part of the Byelorussian Soviet Socialist Republic . Today , it constitutes the western half of the sovereign Republic of ___MASK11___ . World War I ( WWI or WW1 ), also known as the First World War , or the Great War , was a ___MASK50___ war originating in Europe that lasted from 28 July 1914 to 11 November 1918 . More than 70 million military personnel , including 60 million Europeans , were mobilised in one of the largest wars in history . Over nine million combatants and seven million civilians died as a result of the war ( including the victims of a number of genocides ), a casualty rate exacerbated by the belligerents ' technological and industrial sophistication , and the tactical stalemate caused by gruelling trench warfare . It was one of the deadliest conflicts in history , and paved the way for major political changes , including revolutions in many of the nations involved .