You might be interested in threads from the FAQ section on “Racism and Slavery”:

Racism and European Imperialism

-o- Europe had normal diplomatic relations with non-white nations before turning explosively racist to justify their actions against all others. What happened to cause this shift? (22 comments, over 1 year old)

• A flaired commenter in this thread provides a multi-comment long overview of the "flowering" of racism and scientific racism in the 18th and 19th centuries at the height of European imperialism.

-o- What are some of the more notable (scientific) critiques of scientific racism - especially in the 19th century? (3 comments, over 1 year old)

• A flaired user's description of the opposition to scientific racism also serves to highlight the common racism of the day and its origins.

-o- When did the concept of Race begin to emerge? - 25 comments, over 1 year old.

• There are a few summaries of "milestones" of the development of racism from the Age of Exploration to Age of Imperialism with a related article linked in the topmost comment.

Racism and Slavery

-o- Did Racism Cause the Enslavement of Africans? - 2 comments, over 2 months old.

• The commenters here summarize the matter without going into detail.

-o- Do you think racism was the result of slavery? or whether africans were enslaved because of racism? - 7 comments, over 8 months old.

• The commenters here go into detail on the genesis of racism in the US from the Thirteen Colonies to the Antebellum United States.

-o- Why did Europeans enslave Africans instead of other Europeans? - 17 comments, over 2 months old.

• The commenters here go into the difficulties involved in enslaving people in Europe to compare and contrast with the methods used in Africa as well as going into developing attitudes towards race in the Early Modern era.

-o- "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.

-o- 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.

-Followup Questions

If, after looking through the above threads, there are major questions that have been left unanswered or specific topics given insufficient detail, feel free to ask followup questions. Liberal quoting from these threads are encouraged to both allow for clearer answers and to prevent users from wasting time repeating points already addressed.

The following users are flaired on the topic and/or have answered questions on it in the past, and would likely be able to answer these followup questions:

-o- /u/victoryfanfare

-o- /u/restricteddata