Romans \'were not colour prejudiced\', research shows

[Theodosius the Great]

Distinct from the concept of racism (which was never mentioned in the article or by Mateo, the poster of this thread) is the concept of colorism. Colorism is the preference of a skin tone over another within a single ethnic group. Not being a racist doesn't make one color blind. It'd be interesting to know if lighter or darker complexions were considered more beautiful in classical times.

We look at the concept of racism as judged by skin colour through the distorting lens of the Slave Trade, where Sub-saharan Africans were trafficked to the Americas to provide labour. As these people were treated abominably by Europeans, who didn't practice slavery amongst themselves, a sort of post-fact reasoning based on their differences from Europeans, the main one being skin colour, was used to justify the trade. That is, Black Africans were sufficiently 'not the same as us' that they could be treated as though they were sub-human. Thus skin colour became an important way of judging people and being prejudiced about them.

A parallel development may have occurred with the Arabs, the exporters of the black slaves. Since Islam forbids enslaving fellow Muslims the Arabs were reluctant to proselytize among the black tribes. Later they began to espouse racist theories, at least by the 14th century where we read from the Arab scholar Ibn Khaldun :
"beyond [known peoples of black West Africa] to the south there is no civilization in the proper sense. There are only humans who are closer to dumb animals than to rational beings. They live in thickets and caves, and eat herbs and unprepared grain. They frequently eat each other. They cannot be considered human beings." "Therefore, the Negro nations are, as a rule, submissive to slavery, because (Negroes) have little that is (essentially) human and possess attributes that are quite similar to those of dumb animals, as we have stated".

So, this may be another post-justification of slavery which was / is really economically driven.

The Romans, though as guilty as any other people of national chauvanism, were not at all predisposed to be particularly prejudiced towards variations in skin colour.

I believe this remained true in the post-Roman West for centuries. Saint Maurice, the legendary leader of the "Theban Legion" was depicted as a black knight by the 13th century (and perhaps earlier). We can see this in Germany next to Otto I's grave where he is depicted in carved relief :

http://en.wikipedia.org/wiki/Image:Sain ... deburg.jpg

~Theo