This essay analyzes from the perspective of historical revisionism the Communism during the first half of the twentieth century, based on the specialized historiography. It is part of the analysis of Communism as an ideology, system and use of political violence and it is compared with Nazism. In both, Nazism and Communism, similar features are evident; both became in totalitarian systems, which equal attacks perpetrated against humanity. In sum, it appears that the historical memory of the twentieth century marks the responsibilities of Nazism, and Communism responsibility invisible.