None were Jews. Many were apostates of Jewish descent. However, by the 1960’s the communist leadership decided to blame Jews for Poland’s problems, while the entire communist world was on an anti-Jewish and anti-Zionist spree following the failure of the USSR’s proxies to destroy Israel in 1967. More than 1/3 of Poland’s remaining Jews were forced to flee from 1968 and the rest were repressed and virtually all Jews were expelled from the communist party in Poland.
The first Soviet Russia's government - the "Sovnarkom" of the 1917 was all Jews, except two people.
Check bios of the two most prominent: Leon Trotsky and Yakov Sverdlov.