Answer: When the Soviet Union's oil and gas revenue dropped dramatically, the USSR began to lose its hold on Eastern Europe.
Year: November 1989
Answer:
Soviet Union falled by Gorbachev's decision to allow elections with a multi-party system and create a presidency for the Soviet Union began a slow process of democratization that eventually destabilized Communist control and contributed to the collapse of the Soviet Union. And the year was December 26, 1991
Explanation: