The 20th Congress of the Communist Party of the Soviet Union was held during 14–25 February 1956. It is known especially for Nikita Khrushchev's "Secret Speech", which denounced the personality cult and dictatorship of Joseph Stalin.
Delegates at this Congress of the Communist Party of the Soviet Union were given no advance warning of what to expect. Indeed, proceedings were opened by Khruschev's call for all to stand in memory of the Communist leaders who had died since the previous Congress, with Stalin being mentioned in the same breath as Klement Gottwald. Hints of a new direction only came out gradually over the next ten days, which had the effect of leaving those present highly perplexed. The Polish communist leader Bolesław Bierut died in Moscow under mysterious circumstances shortly after attending the 20th Congress.
The congress elected the 20th Central Committee.
On 25 February, the very last day of the Congress, it was announced that an unscheduled session had been called for the Soviet delegates. Khrushchev's morning speech began with vague references to the harmful consequences of elevating a single individual so high that he took on the "supernatural characteristics akin to those of a god." Khrushchev went on to say that such a mistake had been made about Stalin. He himself had been guilty of what was, in essence, a distortion of the basic principles of Marxism-Leninism.
The attention of the audience was then drawn to Lenin's Testament, copies of which had been distributed, criticising Stalin's "rudeness". Further accusations, and hints of accusations, followed, including the suggestion that the murder of Sergey Kirov in 1934, the event that sparked the Great Terror, could be included in the list of Stalin's crimes. While denouncing Stalin, Khrushchev carefully praised the Communist Party, which had the strength to withstand all the negative effects of imaginary crimes and false accusations. The Party, in other words, had been a victim of Stalin, not an accessory to his crimes. He finished by calling on the Party to eradicate the cult of personality and return to "the revolutionary fight for the transformation of society."