the Soviet Union was founded in 1922 and dissoluted in 1991

Correct, the Soviet Union was established on December 30, 1922, following the outcome of the Russian Civil War and the end of the Russian Empire. It was officially called the Union of Soviet Socialist Republics (USSR). The dissolution began with a series of reforms initiated by Mikhail Gorbachev, which included perestroika (restructuring) and glasnost (openness), aiming to reform the stagnated economic, political, and social systems.

The dissolution was formalized on December 26, 1991, when the Supreme Soviet of the Soviet Union met and voted for its own dissolution. This act marked the end of the USSR and the transition to the Commonwealth of Independent States (CIS), with most of the former republics becoming independent countries.