This is one of a set of five sculptures which we encountered in the upper levels of the Colosseum, which were more fully described in the caption on image 0075.

Made of white marble and dating from the late 2nd to early third century, it is believed that the somewhat realistic (or certainly not idealised) face represents an ordinary man. Or, at least, not a God and not an Emperor both of which would doubtless have received a more flattering treatment. However it would still have to be somebody who was worthy of having a sculpture carved of them, suggesting that it may have been a philosopher or man of letters.

Or possibly a senator with bags of money and a talent for self-promotion. Though to be honest that's unlikely since again such a sculpture would be in all likelihood more flattering especially around the mouth. It's the sort of mouth that would have suited Cato but he was long dead by this time thankfully.