Hanson, J. W.,Ortman, S. G.

The last few years have seen a growing interest in the urbanism of the Greek and Roman world. This has led to a consensus of sorts about some of its vital statistics, such as the sizes of the populations of the most important settlements and the size of the overall urban population, the urbanization rate (i.e., the share of individuals that lived in urban, rather than rural, contexts), and the total population. A good example comes from W. Scheidel in the Cambridge economic history of the Greco-Roman world. According to him, it is likely that c.1.5 million people lived in the 5 largest cities of the Greco-Roman world by the 2nd c. A.D. These included Rome, which is usually agreed to have had a population of about 1 million; Alexandria, which might have had c.500,000; Antioch, which could have had at least 150,000; and Carthage and Ephesus (Scheidel does not give explicit figures for those).