Following the signing of the Molotov – Ribbentrop Pact in 1939 and the subsequent invasion and division of Polish territories between the Reich and the USSR , the Soviet Union invaded and occupied the Polish part of Volhynia . In the course of the Nazi – Soviet population transfers which followed this ( temporary ) German-Soviet alliance , most of the ethnic German-minority population of Volhynia were transferred to those Polish areas annexed by Nazi Germany . Following the mass deportations and arrests carried out by the NKVD , and repressive actions against Poles taken by Germany : deportation to the Reich to forced labour camps , arrests , detention in camps and mass executions , by 1943 ethnic Poles constituted only 10 – 12 % of the entire population of Volhynia . During the German invasion , around 40,000 – 60,000 Polish people in Volhynia were massacred by the Ukrainian Insurgent Army . The number of Ukrainian victims of Polish retaliatory attacks until the spring of 1945 is estimated at approx. 2,000 − 3,000 in Volhynia . In 1945 Soviet Ukraine expelled ethnic Germans from Volhynia following the end of the war , because Nazi Germany had used ethnic Germans in eastern Europe as an excuse to invade those areas . The expulsion of Germans from eastern Europe was part of a mass population transfer after the war
were massacred
Massacres of Poles in Volhynia and Eastern Galicia
Volhynia