Using many unpublished documents and witnesses' accounts of the events in Poland in March 1968 (from the author's archive), describes the political crisis in Poland between 1956-66, the struggle for power among factions inside the Polish Workers' Party, and the plot of Mieczysław Moczar, leader of the "partisans" faction of "nationalist communism" orientation, to achieve power by launching a massive antisemitic campaign. Moczar used antisemitism (officially called anti-Zionism) as a political tool and provoked mass repression of the intelligentsia and students. Concludes that the 1968 crisis meant "the end of ideological thought" in Poland. Up to 1968, communist ideology had its supporters amongst the intellectuals, but after 1968 many of them left the party, and most of them lost their illusions regarding communism.