Agit Prop is a contracted, or portmanteau, word that has come into the English language from Russian and refers to the promotion of political ideas, particularly those of the Left, through literature, drama, music, or art. In the 1920s, immediately after the Communists came to power in the Soviet Union, the Department of Agitation and Propaganda was established to advance the ideological education of the masses.

Source: Design Dictionary: Perspectives on Design Terminology – Michael Erlhoff, Michael Erlhoff, Timothy Marshall.