Task: Question Generation
Input (English): The Baltic Way or Baltic Chain (also Chain of Freedom Estonian: Balti kett, Latvian: Baltijas ceļš, Lithuanian: Baltijos kelias, Russian: Балтийский путь) was a peaceful political demonstration on August 23, 1989. 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.
Output (English): What anniversary did the chain take place on?