From our perspective, slavery is one of the most controversial institutions of the past. We see slavery as an inhumane, immoral, and intolerable business, an unacceptable human flesh for cash type of business that none of us could tolerate. For the ancients, however, slavery was part of the everyday landscape, a completely recognized social institution smoothly integrated into the overall social fabric.
10. Slave Population
Ancient Roman society had a high proportion of slave population. Some have estimated that 90 percent of the free population living in Italy by the end of the first century BC had ancestors who had been slaves (McKeown 2013: 115).
The proportion of slaves was so significant that some Romans left written accounts on the dangers of this situation: “It was once proposed in the Senate that slaves should be distinguished from free people by their dress, but then it was realized how great a danger this would be, if our slaves began to count us” [Seneca, On Mercy: 1.24].
Modern estimations on slave population in Italy give us a figure of about 2 million by the end of the Republican period, a slave-to-free ratio of about 1:3 (Hornblower and Spawforth 2014: 736).