Ancient Rome was originally an Italic settlement dating from the 8th century BC that grew into the city of Rome and which subsequently gave its name to the empire over which it ruled and to the widespread civilisation the empire developed. The Roman empire expanded to become one of the largest empires in the ancient world, though still ruled from the city, with an estimated 50 to 90 million inhabitants (roughly 20% of the world's population
[There are several different estimates for the population of the Roman Empire.
]) and covering 5.0 million square kilometres at its height in AD 117.
- Scheidel (2006, p. 2) estimates 60.
- Goldsmith (1984, p. 263) estimates 55.
- Beloch (1886, p. 507) estimates 54.
- Maddison (2006, p. 51, 120) estimates 48.
- Roman Empire Population estimates 65 (while mentioning several other estimates between 55 and 120).
- McEvedy and Jones (1978).
- an average of figures from different sources as listed at the US Census Bureau's Historical Estimates of World Population
- Kremer, Michael (1993). "Population Growth and Technological Change: One Million B.C. to 1990" in The Quarterly Journal of Economics 108(3): 681–716.