Hungarian Socialist Workers' Party

The Hungarian Socialist Workers' Party (Hungarian: Magyar Szocialista Munkáspárt, MSzMP) was the ruling Marxist–Leninist party of the Hungarian People's Republic between 1956 and 1989. It was organised from elements of the Hungarian Working People's Party during the Hungarian Revolution of 1956, with János Kadar as general secretary.

The party initially supported the revolution, but turned against Imre Nagy's government after he denounced the Warsaw Pact. The party formed a 'Revolutionary Peasant-Worker Government' that took over the country, with Soviet support, on 4 November 1956.

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