The Soviet annexation of some 51.6% of the territory of the Second Polish Republic, where about 13,200,000 people lived in 1939 including Poles and Jews, was an important event in the history of contemporary Ukraine and Belarus, because it brought within Ukrainian and Belarusian SSR new territories inhabited in part by ethnic Ukrainian and Belarusian people, and thus unified previously separated branches of these nations. The postwar population transfers imposed by Joseph Stalin, and the Holocaust, solidified the mono-ethnic character of these lands by nearly a complete eradication of the Polish and Jewish presence there. Ukraine and Belarus achieved independence in 1991 after the fall of the Soviet Union and became nation states delineated by borders of the 50-year-old republics. "The process of amalgamation – wrote Orest Subtelny, a Canadian historian of Ukrainian descent – was not only a major aspect of the post-war period, but an event of epochal significance in the history of Ukraine."