Aftermath of the Polish–Soviet War

According to the British historian A. J. P. Taylor, the Polish-Soviet War "largely determined the course of European history for the next twenty years or more.[...] Unavowedly and almost unconsciously, Soviet leaders abandoned the cause of international revolution." Certainly the Bolsheviks' defeat in the war prevented Poland from becoming another Soviet republic and likely prevented Germany, Czechoslovakia and other nearby states from sharing a similar fate.

Soviet Communism was not eliminated, however, but only contained for a generation. Russia kept control of substantial western territories and their vast resources. Soon after the war officially ended, groups of Soviet-sponsored bandits and undercover agents began raiding Polish eastern frontier, prompting Poland to create a special, elite Border Defence Corps (Korpus Ochrony Pogranicza) to combat those constant incursions. A second Soviet effort at expansion was more successful. In August 1939 the Soviet Union signed the Molotov-Ribbentrop Pact with Nazi Germany and in cooperation with the latter invaded Poland on September 17, 1939, ensuring Poland's defeat in the Polish Defensive War of 1939. The Soviet occupation of eastern Poland rivaled in atrocities the German occupation of the remainder of the country. Persons who were deemed dangerous by the Communist authorities were subject to sovietization, forced resettlement, and imprisonment in labor camps (the Gulags), or were simply executed, as in the case of Polish officers in the Katyn massacres. Having served in the Polish-Soviet War on the side of Poland was punishable with death. After Poland had been occupied by the Red Army in 1944, Soviet atrocities included persecutions and prosecutions of Polish Home Army soldiers and executions of their leaders. In the aftermath of World War II, the Soviet Union succeeded in acquiring control of more territory than Imperial Russia had and partly fulfilled Lenin's original dream of bringing communist revolution to Germany. Until 1989, while Communists held power in a People's Republic of Poland, the Polish-Soviet War was either minimized in significance or misportrayed in Polish and other Soviet bloc countries' history books, for instance typically citing Poland as the aggressive initiator of the war on behalf of the Entente.

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