International propaganda clearly shows a tendency of rapid growth since its first institutionalisation in the Sacra Congregatio de Propaganda Fide of Pope Gregory XV in the seventeenth century. In different historical periods and social systems (and likewise in different communication and political theories) diverse and even controversial concepts of propaganda have been developed. Although there is no commonly accepted definition of propaganda, a large majority of definitions have some identical elements (e.g. that it attempts to influence people's opinions, attitudes, values, actions). However, there does not exist an agreement about the essence of propaganda and its specific characteristic in relation to communication in general, to ideology, class struggle and other key social phenomena. The relationship of propaganda to ideology seems to be the most ambiguous. On the one hand, controversies result from the concept of ideology itself (e.g. differences between Marx's, Lenin's, Mannheim's and other considerations of ideology). On the other hand, conceptual differences are related to the development of a specific kind of social communication — mass communication and mass media. The general characteristic of mass communication as public communication, which supposedly goes beyond particular interests because of its "universality", conceals the ideologic-legitimising function of mass media.