 Slavery was a major economic and social institution in Europe during the classical era and a great deal is known about the ancient Greeks and Romans in relation to the topic.Rome added Portugal to its empire (2nd century BC), the latter a province of Lusitania at the time, and the name of the future kingdom was derived from "Portucale", a Roman and post-Roman settlement situated at the mouth of the Douro River.The details of slavery in Roman Portugal are not well-known; however, there were several forms of slavery, including enslaved miners and domestic servants.