<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The Soviet Union was dissolved on December 26, 1991 . It was a result of the declaration number 142 - Н of the Soviet of the Republics of the Supreme Soviet of the Soviet Union . The declaration acknowledged the independence of the former Soviet republics and created the Commonwealth of Independent States (CIS), although five of the signatories ratified it much later or did not do so at all . On the previous day, Soviet President Mikhail Gorbachev, the eighth and final leader of the Soviet Union, resigned, declared his office extinct, and handed over its powers--including control of the Soviet nuclear missile launching codes--to Russian President Boris Yeltsin . That evening at 7: 32, the Soviet flag was lowered from the Kremlin for the last time and replaced with the pre-revolutionary Russian flag . </P> <P> Previously, from August to December, all the individual republics, including Russia itself, had seceded from the union . The week before the union's formal dissolution, 11 republics signed the Alma - Ata Protocol formally establishing the CIS and declaring that the Soviet Union had ceased to exist . Both the Revolutions of 1989 and the dissolution of the USSR (Russian: распад СССР) also signalled the end of the Cold War . </P>

Who was the head of the soviet union when it collapsed