In 1956, the USSR invade the country of Hungary. After World War II, the Soviet Army occupied Hungary, with the country coming under the Soviet Union's sphere of influence. At the time, Hungary was a multiparty democracy, and elections in 1945 produced a coalition government under Prime Minister Zoltán Tildy.

The Hungarian Revolution of 1956 was a spontaneous nationwide revolt against the Communist government of Hungary and its Soviet imposed policies. After announcing their willingness to negotiate the withdrawal of Soviet forces, the Soviet authorities changed their minds and moved to crush the revolution. On November 4, 1956, a large joint military force of the Warsaw Pact, led by Soviet soldiers from Moscow, entered Budapest to crush the armed resistance. Soviet intervention, code named "Operation Whirlwind", was launched by Marshal Ivan Konev. Five Soviet divisions stationed in Hungary before October 23,1956 in the first intervention ("Operation Wave") were augmented to a total strength of 17 divisions.

By crushing of the Hungarian Revolution, the USSR strengthened its control over the Warsaw Pact.

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