Answer:
Social Darwinism is an extension of the Darwinian hypothesis of the biological survival for the fittest and the natural selection for evolution of man to the socio-political quasi philosophy in the social conflicts between social communities or social groups in society popularized by Herbert Spenser & Francis Galton in the concept of laissez faire for the welfare of the society.
The clash of civilizations in religious-cultural practices,the discrimination and conflicts between the echelons in society and the weak slaves or the unequal distribution in wealth as the Marxian philosophy of conflicts towards a classless society may be termed barbaric as these conflicts are facts and not normative theories.