These words are closely related to each other and to such terms as barbarian, barbarism, and barbarity. Both barbaric and barbarous are adjectives meaning "uncivilized," "primitive," "without civilizing influences." Barbaric is occasionally used in a favorable sense to refer to those elements in a culture, such as vigor, ardor, and love of splendor, that the speaker or writer finds praiseworthy (a splendidly barbaric people). Barbarous is more often used to refer to the cruel and vicious customs and practices of uncivilized groups (the inhuman deeds of barbarous Huns).
Dictionary of problem words and expressions. Harry Shaw. 1975.