While you wait for a more targeted answer, you might be interested some background reading in the threads from the FAQ section on “Racism and Slavery":
#Race and Racism in Antiquity
I've often heard it said that the ancient Romans were so culturally and ethnically non-homogenous that "racism" as we now understand it did not exist for them. Is this really true? - 137 comments, over 2 years old.
This thread dives headlong into the matter, inciting debates over whether the ethnic stereotypes common in the ancient world are of the same kind as modern racism or not while supplying plentiful evidence and analysis for both sides.
Was there much racism in the Roman Empire directed at people from other regions? - 47 comments, over 1 year old.
The commenters in this thread differentiate between the xenophobia present the ancient world from the modern understanding of racism.
I know the Romans had no conception of race, but did they view Black Africans any differently than they did the Persians, Libyans, or Celts? - 80 comments, over 11 months old.
This thread goes into the way Rome interacted with peoples that would be classified in the modern day as being of different races.
Racism in the ancient world? - 37 comments, over 1 year old.
This thread pulls examples from all across the world and its history along with copious amounts of sources for further reading.
Did the Romans have stereotypes about the behavior of people from particular tribes or geographic areas? - 9 comments, over 11 months old.
Several commenters detail the most common stereotypes that Romans held of others at the borders of their empire and beyond.
"I don't think that ancient slavery is really comparable to the chattel slavery that we saw in the Americas." How did ancient slavery differ from the atlantic slave trade? - 91 comments, over 6 months old.
This thread is mostly about Roman slavery including how slaves were acquired, what they were used for, and what ethnicity/race they were and thus allowing comparison with the situations presented in the threads above.
How true is the claim that "racism created race", as opposed to the other way around? - 9 comments, over 6 months old.
This thread brings up and summarizes the a book with a contrary claim to the traditional narrative that modern racism primarily derives from the Early Modern era.
Were there any Asians and/or Africans in Ancient Europe?
The blog medievalpoc.tumblr.com asserts that Black people were common for essentially all of European history. Is this true? - 59 comments, over 11 months old.
Despite the title, this thread mostly draws upon ancient examples and talks about ancient concepts of race.
How would I be treated in Ancient Roman as a black man? - 10 comments, over 3 months old.
This thread brings up Roman art of black Africans and also links to an article about “ancient geographical prejudice” influencing modern conceptions of race.
do historians mean something different then normal people when they use the word "racism"? - 11 comments, over 2 years old.
Commenters here talk about concepts of race as dealt with in Anthropology and other related fields.
How did racism develop? - 3 comments, over 1 year old.
The question itself is left unanswered, but a primary source example is brought up from a Roman architecture book of all places.
What race/ethnicity were the Ancient Romans? - 8 comments, over 1 year old.
The commentators summarize the ethnic diversity present in Italy and the city of Rome itself.