“There were not enough citizens of Rome or even Italy to control the whole Roman Empire, but there were many people in the provinces that had accepted Roman rule. Inscriptions carved into stone to commemorate the dead on tombs, or to record who set up an altar to the gods, show that people came not only from Italy, but also from Gaul, North Africa and Spain; in the later Roman period new troops were recruited from Germany and even from beyond the frontiers of the Empire. The Roman conquest of Britain led to the migration of many soldiers and administrators, merchants and also women and children.
It is difficult to estimate total numbers of people who came to Britain during the era of Roman control: troop movements are quite well-documented but there are no surviving records of how many civilians journeyed to the province. Stone inscriptions were only erected by a few wealthy individuals who had adopted Roman ways of doing things; from the whole of Britain only about 2,500 stone inscriptions survive. The analysis of skeletons offers archaeologists an opportunity to identify the origin of many more individuals by studying skull shape as well as isotope and DNA signatures (more on this below) [follow the link]. Evidence suggests that, over time, locals and incomers intermarried, and that the populations in major urban and military sites were very diverse.”
http://www.ourmigrationstory.org.uk/oms/roman-britain-the-ivory-bangle-lady
