The Soviet Union officially ceased to exist on December 26, 1991. This marked the end of over 70 years of communist rule following the Bolshevik Revolution in 1917. The dissolution resulted from a multitude of factors, including economic turmoil, political unrest, and nationalist movements within various Soviet republics. The restructuring policies initiated by Mikhail Gorbachev—glasnost (openness) and perestroika (reform)—failed to revitalize the economy and led to widespread calls for autonomy. The collapse fragmented the USSR into independent nations, fundamentally reshaping global geopolitics and signaling the end of the Cold War era, making way for new political and economic systems.