[1] He was born Ephraim Feuerlicht in Przemyśl, Kingdom of Galicia and Lodomeria, on 18 April 1913 into a Jewish family.
[2][3] He was one of the founders of a youth organization targeting Zionist junior high school students.
[2] When France was occupied by the Nazis Marek was arrested and sentenced to death and was freed only after the liberation of Paris in 1944.
[2][3] He and another party member Ernst Fischer produced many writings on Karl Marx and Vladimir Lenin in 1968 and 1969 to show that the genuine Marxism–Leninism was very different from the Stalinism-based Communism.
[6] Due to these views and his stance against the invasion of Czechoslovakia by the Soviet Union he was removed from the Communist Party led by Franz Muhri in 1970.