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"
Communist Party of the Soviet Union and effective control of the party organization remained in Gorbachev's control. Chernenko died on 10 March 1985 and was succeeded in office by Gorbachev on 11 March 1985. Gorbachev was elected CPSU General Secretary on 11 March 1985, one day after Chernenko's death. When he acceded, the Soviet Union was stagnating but was stable and may have continued largely unchanged into the 21st century if not for Gorbachev's reforms. Gorbachev conducted a significant personnel reshuffling of the CPSU leadership, forcing old party conservatives out of office. In 1985 and early 1986, the new party leadership called for "uskoreniye" (). Gorbachev