I guess. In the modern world we learn to pick up on the small on average differences between ethnicities that have had families live I uncertain climates for hundreds or thousands of years. But the thibgs white supremacists are projecting onto the past weren't even around until colonial days. Helen could have looked tan, it's probably most likely, but she also could have looked black. We really don't know for sure. You can look up the history of race. It used to just be nationality. race was not even a concept. Maybe you noticed some people had darker skin. Or some regions had people with darker skin on average. But people still migrated in the ancient world.

Black emperors? I don't think so.