Language is a system that consists of the development, acquisition, maintenance and use of complex systems of communication, particularly the human ability to do so; and a language is any specific example of such a system.
A society is a group of individuals involved in persistent social interaction, or a large social group sharing the same geographical or social territory, typically subject to the same political authority and dominant cultural expectations. Societies are characterized by patterns of relationships (social relations) between individuals who share a distinctive culture and institutions; a given society may be described as the sum total of such relationships among its constituent of members. In the social sciences, a larger society often evinces stratification or dominance patterns in subgroups.
Evolution teaches us the original purpose of language was to ritualize men's threats and curses, his spells to compel the gods; communication came later.
Gene Wolfe, "The Death of Doctor Island", Universe 3 (1973), ed. Terry Carr; reprinted in The Best of Gene Wolfe (2009).