Soviet and Eastern bloc Marxism

As the first socialist state, dedicated to the construction of a communist society, the USSR offers some unusual and fascinating perspectives on the history of Marxism, as does Eastern Europe. The Soviet state devoted a huge amount of time, resources, energy and words to the development, production, dissemination and propagation of Marxism Soviet-style. Is there an identifiable Soviet Marxist canon? What, if anything, did this massive effort contribute to the development of Marxist thought in general? In political terms, the self-identification of the Soviet state as an entity guided by, or better perhaps armed with, Marxism-Leninism, coupled with the troubled history of the USSR, has significantly shaped popular perceptions of the effects of Marxism when in power. How accurate is it to see Soviet Marxism as a sterile, dogmatic, monolithic, uncritical body of doctrine designed to rationalise the oppressive rule of the CPSU (Communist Party of the Soviet Union)? Finally, the Soviet case provides an interesting example of the shift from revolutionary doctrine to ruling ideology which Soviet Marxism underwent after 1924. How did this change impact upon Soviet Marxism?