On February 24, 1956 before assembled delegates to the Communist Party's Twentieth Congress as well as observers from foreign Communist parties, Nikita Khrushchev delivered a speech denouncing Stalin for his transgressions. The speech was "secret" in the sense that it was read in a closed session without discussion and was neither published as part of the congress' proceedings nor reported in the Soviet press. However, copies were sent to regional party secretaries who were instructed to brief rank-and-file members. Moreover, the US State Department received a copy of the speech from East European sources and soon released it.
The speech, replete with lengthy quotations from correspondence and memoranda, gave details about the unwarranted arrest and execution of high-ranking loyal party members during the Terror of the late 1930s; the unpreparedness of the country at the time of the Nazi invasion in June 1941; numerous wartime blunders; the deportation of various nationalities in 1943 and 1944 and the banishing of Tito's Yugoslavia from the Soviet bloc after the war. Absolving the party itself of these grave actions, Khrushchev attributed them to the "cult of personality" that Stalin allegedly encouraged and his "violations of socialist legality," code words for dictatorship and terror. Noticeably absent from this indictment were the collectivization drive that was accompanied by massive state violence and famine, the repression of intellectuals, and any implication that other party leaders -- himself included -- shared responsibility for the crimes that Khrushchev mentioned.
The speech sent shock waves throughout the Communist world and caused many western Communists to abandon the movement. In Tbilisi, students demonstrated against the removal of a monument to Stalin, Georgia's native son. In Poland, demonstrations by workers in Poznan over declining wages and deep divisions between recalcitrant Stalinists and anti-Stalinists within the Polish Workers' Party threatened to engulf the country in crisis, and in Hungary mass demonstrations led to a popular uprising in October 1956. The prime minister, Imre Nagy, sought to regain control through concessions that included abolishing the one-party system and freeing from prison the virulently anticommunist Cardinal Jozsef Mindszenty, but as the insurgency expanded, the Soviet Presidium decided to send in troops. The Hungarian uprising, which occurred simultaneously with the Anglo-French intervention against Egypt over its claims to the Suez Canal, was the most serious crisis in the Soviet bloc until the Prague Spring of 1968. It temporarily weakened Khrushchev in his struggle against the Stalinist stalwarts in the Presidium who conspired, but failed, to oust him in June 1957.