[brobinson]

>He was black.

A quick search shows results saying his ancestors were all from northern Africa and the Middle East. He doesn't even look black in various busts/statues depicting him. He definitely looks north African. I'm pretty into Roman history, and this is the first time I've ever encountered someone suggesting there was a "black" (in the modern sense of the word) emperor.

[Amezarak]

Not commenting on Severus specifically, I’ve noticed that it seems really common in modern times for some reason for people to believe “white” means European, even though “white” people lived indigenously throughout North Africa, the Middle East, and Asia - including people with blue eyes or red/blonde hair.

Similarly, “African” is for some reason taken to exclusively mean “sub-Saharan” even though as you note most people would not identify most North African ethnic groups as black.