Question: When was Michail Gorbachev elected General secretary?
About the article "Dissolution of the Soviet Union", section "Soviet Union centre – the new General Secretary".

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Ligachev was First Secretary of the Novosibirsk Komsomol, before becoming Deputy Chairman of the Novosibirsk Soviet, and then Secretary of the Novosibirsk Obkom between 1959 and 1961.
Ligachev's first major post was attained in 1961, when he began working in the CPSU Central Committee.
In 1965, he became First Secretary of the Party in Tomsk, Siberia.
He was to hold this position until 1983, when he was discovered by Yuri Andropov and made head of the Party Organization Department and a Secretary of the Central Committee.
In 1966, Ligachev was elected a candidate member of the Central Committee, and ten years later in 1976 he was promoted to a full member.
When Mikhail Gorbachev became General Secretary in 1985, Ligachev was promoted to become a Secretary of higher status, and was generally viewed as one of Gorbachev’s primary allies: he had helped organize a pro-Gorbachev faction in hope of having Gorbachev succeed Andropov in 1984, although this attempt failed (instead, Konstantin Chernenko was chosen as a stop-gap candidate).
Ligachev was made head of the Secretariat.
Ligachev supported reform of the Soviet Union and initially supported Gorbachev; however, as Gorbachev’s policies of perestroika and glasnost began to resemble social democratic policies he distanced himself from Gorbachev, and by 1988 he was recognized as the leader of the more conservative, anti-Gorbachev faction of Soviet politicians.
During this period Ligachev uttered his notorious catch phrase "Boris, you are wrong", targeting Boris Yeltsin in a political discourse.
Ligachev served in the Politburo between 1985 and 1990.
Ligachev, having made some speeches criticising Gorbachev, was demoted from his more prestigious position as Secretary for Ideology to Secretary for Agriculture in 1988.
Perhaps the highlight of Ligachev's career was the 28th Congress of the CPSU in 1990.
Ligachev criticized Gorbachev for circumventing the Party via Soviet Presidency, and he argued Glasnost had gone too far.
During the Party Congress, Ligachev challenged Gorbachev for the office of General Secretary, standing as the "Leninist" candidate.
Having been defeated, Ligachev left the Politburo and went into temporary retirement. 
Mikhail Gorbachev became the party's general secretary in 1985 following an interregnum after Brezhnev's death in 1982 when the party was led first by Yuri Andropov and then by Konstantin Chernenko.
When Brezhnev died Andropov was proclaimed General Secretary within days and by the official coverage in the Soviet media it was clear that he was "the" leader.
Andropov died on February 9, 1984 and Chernenko was elected his replacement on February 13 but Chernenko was a compromise stopgap candidate as Gorbachev – Andropov's protege – lacked sufficient support in the Politburo.
However, Chernenko was already an ill man and his duties were increasingly carried out by others, particularly Gorbachev who was nominated by Andrei Gromyko to become General Secretary when Chernenko died.
There are indications Gorbachev may have been in control prior to Chernenko's death as he was announced as the new General Secretary the day after Chernenko died on March 10, 1985.
Gorbachev instituted policies of glasnost, perestroika, and acceleration.
Glasnost allowed freedom of speech in the Soviet Union and a flourishing of political debate within the Communist Party to a degree not seen since the Russian Revolution, perestroika was an attempt to restructure the political and particularly the economic organisation of the country, while acceleration meant faster development of the economy.
This period of liberalisation ultimately ended in the dissolution of the Soviet bloc in Eastern Europe.
At the 27th Congress of the CPSU in 1986, Boris Yeltsin became a candidate member of the Politburo and offended party members in a speech that attacked the hidden privileges of the party elite.
At the 1988 Party Conference Gorbachev launched reforms to reduce the party's control over the government including proposals for multicandidate elections to regional and local legislatures and the positions of local and regional party first secretaryships.
While Gorbachev was able to receive approval for his reforms from the party, the membership of the CPSU was becoming increasingly resistant to Gorbachev's policies and rather than being a locus for change became a bulwark of conservatism.
Increasingly, Gorbachev bypassed the party in order to implement his reforms relying instead on governmental bodies. 
Gorbachev's election to the General Secretaryship was the quickest in Soviet history.
The Politburo recommended Gorbachev to the Central Committee, and the Central Committee approved him.
The Politburo meeting, which elected Gorbachev to the General Secretaryship, did not include such members as Dinmukhamed Konayev, Volodymyr Shcherbytsky and Vitaly Vorotnikov.
Of these three, Konayev and Shcherbytsky were Brezhnevites, and Vorotnikov, while not supporting Gorbachev, took it for granted that Gorbachev would succeed Chernenko.
It is conceivable, according to historian Archie Brown, that Konayev and Shcherbytsky would rather have voted in favour of Viktor Grishin as General Secretary, then Gorbachev.
At the same meeting, Grishin was asked to chair the commission responsible for Chernenko's funeral; Grishin turned down the offer, claiming that Gorbachev was closer to Chernenko than he was.
By doing this, he practically signaled his support for Gorbachev's ascension to the General Secretaryship.
Andrei Gromyko, the longtime foreign minister, proposed Gorbachev as a candidate for the General Secretaryship.
The Politburo and the Central Committee elected Gorbachev as General Secretary unanimously.
Ryzhkov, in retrospect, claimed that the Soviet system had "created, nursed and formed" Gorbachev, but that "long ago Gorbachev had internally rebelled against the native System."
In the same vein, Gorbachev's adviser Andrey Grachev, noted that he was a "genetic error of the system.
"Gorbachev's policy of "glasnost" (literally "openess") meant the gradual democratisation of the party.
Because of this, the role of the Central Committee was strengthened.
Several old apparatchiks lost their seats to more open-minded officials during the Gorbachev era.
The plan was to make the Central Committee an organ where discussion took place; and in this Gorbachev succeeded.
By 1988, several people demanded reform within the Communist Party itself.
At the 19th Conference, the first party conference held since 1941, several delegates asked for the introduction of term limits, and an end to appointments of officials, and to introduce multi-candidate elections within the party.
Some called for a maximum of two term-periods in each party body, including the Central Committee, others supported Nikita Khrushchev's policy of compulsory turnover rules, which had been ended by the Brezhnev leadership.
Other people called for the General Secretary to either be elected by the people, or a "kind of party referendum".
There was also talk about introducing age limits, and decentralising, and weakening the party's bureaucracy.
The "nomenklatura system" came under attack; several delegates asked why the leading party members had rights to a better life, at least materially, and why the leadership was more-or-less untouchable, as they had been under Leonid Brezhnev, even if their incompetence was clear to everyone.
Other complained that the Soviet working class was given too large a role in party organisation; scientific personnel and other white-collar employees were legally discriminated against. 
As Brezhnev's health worsened during the late 1970s, the collective leadership became even more "collective".
Brezhnev's death did not alter the balance of power in any radical fashion, and Yuri Andropov and Konstantin Chernenko were obliged by protocol to rule the country in the very same fashion as Brezhnev.
When Mikhail Gorbachev was elected to the position of General Secretary in March 1985, some observers wondered if he could be the leader to overcome the restraints of the collective leadership.
Gorbachev's reform agenda had succeeded in altering the Soviet political system for good; however, this change made him some enemies.
Many of Gorbachev's closest allies disagreed with him on what reforms were needed, or how radical they should be.
The claim that the Secretariat was the Party's "center of power" was proven false in 1988 when it was shown that Yegor Ligachev chaired its meetings, rather than Gorbachev. 
Her essay "I Cannot Forsake My Principles" (I Cannot Waive Principles) was published in the newspaper "Sovetskaya Rossiya" on March 13, 1988, at a time when Gorbachev and Alexander Yakovlev were abroad, and cited an anti-Gorbachev report by the secretary of the Party's Central Committee, Yegor Ligachev.
Anti-perestroika party officials welcomed the essay, whereas supporters of Gorbachev and Yeltsin feared that it represented a major defeat for them.
Gorbachev subsequently revealed that many members of the Politburo seemed to share Andreyeva's views, and that he had to coerce them into approving the publication of an official rejoinder.
The published response appeared in Pravda on 5 April 1988, and was not nearly as forceful as its authors have claimed.
In the aftermath of this discussion, the General Secretary at least temporarily tightened his own control over the Secretariat of the Central Committee.
The entire episode may have contributed to his decision to reform the Secretariat in the autumn of 1988.