History of socialism under challenge from Solidarność, or Solidarity, a labor union under the leadership of Lech Wałęsa. The union was sufficiently threatening to the government that on 13 December 1981, the head of state, Wojciech Jaruzelski declared martial law, suspended the union, and imprisoned most of its leaders. Mikhail Gorbachev (born 1931), who took control in 1985, was the first Soviet leader to have been born after the October revolution. He is remembered for three initiatives: "glasnost", "perestroika", and the "Frank Sinatra doctrine". "Glasnost", or "openness", was Gorbachev's term for allowing public debate in the Soviet Union to an unprecedented degree. "Perestroika"
Mikhail Gorbachev the flag of the Soviet Union was lowered from the Kremlin and was replaced with the Russian tricolor flag. The next day, 26 December, the Soviet of the Republics, the upper chamber of the Supreme Soviet, declared that the Soviet Union had ceased to exist as a functioning state, and formally voted both itself and the Union out of existence. Two days after Gorbachev left office, on 27 December 1991, Yeltsin moved into Gorbachev's old office. Gorbachev had aimed to maintain the CPSU as a united party but move it in the direction of Scandinavian-style social democracy. But when the