Islam spread to most of the Iberian Peninsula, and as far India in the east.
Social Darwinism was most likely applied to treat immigrants from different regions differently, however, Social Darwinism does not specifically relate to immigrants but also to all members of society. In the American context, the notion was implemented to popularize the notion of "survival of the fittest" or that the strongest members of a society will succeed and the political system should support this theory.
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