Query: What part of Europe was split up by the pact?
Context: An estimated 2 million people joined hands to form a human chain extending 600 kilometres (370 mi) across Estonia, Latvia and Lithuania, which had been forcibly reincorporated into the Soviet Union in 1944. The colossal demonstration marked the 50th anniversary of the Molotov–Ribbentrop Pact that divided Eastern Europe into spheres of influence and led to the occupation of the Baltic states in 1940.