Original sentence: A large portion of the wave of new migrants to industrialize, integrate and Sovietize these territories were ethnic Russians who mostly settled around industrial centers and military garrisons...The infrastructure was heavily damaged and it required human and capital resources to be rebuilt.The territory of Ukraine was a battlefield during the World War II, and its population, including Russians, significantly decreased
Edited sentence: During the German occupation, almost entire Polish population of Volhynia was ethnically cleansed by the Ukrainian Insurgent Army.This created a vacuum of workers and, after Red Army took control of Western Ukraine in 1944, a new wave of migrants to industrialize , integrate and Sovietize these territories was necessary.This included a large portion of ethnic Russians who mostly settled around industrial centers and military garrisons