Final answer:
The collapse of the Soviet Union was triggered by a collapse in the Soviet economy, as well as political changes and independence movements within the satellite states. The signing of the Belavezha Accords in December 1991 marked the official end of the Soviet Union.
Step-by-step explanation:
The collapse of the Soviet Union was primarily caused by a collapse in the Soviet economy, which led to political and social turmoil. The Soviet Union faced numerous economic challenges, including inefficiency, corruption, and a lack of innovation. These issues, coupled with the arms race and the cost of maintaining a large military, strained the Soviet economy to its breaking point.
Additionally, the policies of Soviet leader Mikhail Gorbachev, such as glasnost (openness) and perestroika (restructuring), unintentionally weakened the centralized power of the Soviet government. This allowed for increased political dissent and a push for independence from the satellite states of the Soviet Union. The Baltic states of Estonia, Latvia, and Lithuania declared independence, and other Soviet republics followed suit.
The final blow to the Soviet Union came in December 1991, when the leaders of Russia, Ukraine, and Belarus signed the Belavezha Accords, dissolving the Soviet Union and establishing the Commonwealth of Independent States (CIS) as its successor.
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