The paper tests a simple but fascinating hypothesis, name-ly, that racism is a strictly modern reality. We will not find spe-cifically racist theories before the eighteenth century. We also intend to establish a suggestive contrast with Spanish thought of the 16th century. The goal is to corroborate an issue that, per-haps, will amaze more than one: the verifiable circumstance that racism is absent in the doctrines of the jurists, moralists, theolo-gians, and humanists (as well as early ethnologists) of imperial Spain in the 16th century.