You may be interested in this answer by /u/The_Alaskan from several years ago. There's some further followup in the replies.

I forget how personal history is and /u/The_Alaskan reply was a reminder that we are all products of our times.

Thank you /u/The_Alaskan for that insightful post into race relations.

A follow up question that I didn’t see in the posted answer. Were there any incidents of American ambassadors being discriminated against based on skin color, ethnicity, or religion in other countries?