Frescoes and mosaics are not reliable sources for the composition of the overall population, as they generally will over-represent specific social-strata and specific demographics, so without a control we don't really know what they tell us.

Considering Libya where the Roman presence itself in the North quite possibly was quite light-skinned and where the elite under Roman rule likewise quite likely was white than average for the population, with a lot of people coming from elsewhere in the empire. But a lot of the rest of the population was berbers, which range from relatively light brown to the darkest sub-Saharan black.

We know that sub-Saharan berber groups went to the North, because we know that a whole Roman legion was stationed on the coast to repel raiders from the South.

But I don't think we do know how large a number of the Northern population was made up of Romans from elsewhere and lighter skinned berbers vs darker skinned berbers and/or other groups at any given point in time. If there is data on this, I'd love to see it.

Though we also know that the bedouin population that dominates the North of Libya today, largely came with the Muslim conquest in the 7th century, so modern day Libya is at the very least a very poor indicator of what it looked like 2000 years ago.

(focusing on Libya because Septimius Severus - one the persons mentioned in Beards response - was born in Libya, and because I've covered it in other comments)

No-one is suggesting that everyone or even the majority of people in North Africa have "black" skin, but I'm awaiting references showing that North Africa was majority white at the time of the Roman empire. The guy in the cartoon has brown skin.

White as in not black. Not as in red-haired blue-eyed WASPs.

Of course it can have "brown skin". Egyptians, Tunisians, and co, including people in Souther Spain, Greece, Italy, Lebanon, the Middle East, and so, had, and still have brown skin, but are not black like e.g. Ethiopians (which ancients also describe), nor are depicted as such.

The character in the cartoon is not depicted as having particularly dark skin. No-one uses white to mean "not black".

Edit: There is also archeological evidence for Romans with Sub Saharan ancestry reaching the UK. See e.g.

https://evoandproud.blogspot.com/2009/11/was-roman-britain-m...

>No-one uses white to mean "not black"

Well, in Europe (and hopefully modern US) white includes the peoples not considered black (or asian etc).

Arabs for example are still white, Egyptians too, etc. Outside of racist circles were only WASPs or northern europeans were considered white (which was historically the case for most of the 20th century where white was hijacked for "northern European ancestry").

Egyptians for example, are also white. As are Arabs, middle eastern people, etc. But e.g. Ethiopians, or Ghana people are not (the majority of course, not that all citizens are not).

http://www.independent.co.uk/news/science/archaeology/ancien...

http://www.aljazeera.com/indepth/opinion/2015/07/arabs-white...

Many of the groups you're mentioning don't even self-identify as white in English-speaking countries. Not really sure what you're trying to get at any more.

They mostly wouldn't be identified as white in England either.

That's not true for much of the Europe I've experienced. Many people from Spain, Greece, or Italy, for example, would not be considered 'white'.

Generally I'd say that the whiter the population is, the higher the barrier to entry, so to speak, to being considered 'white'.