Deportation is the expulsion of a person or group of people from a place or country. Today the expulsion of foreign nationals is usually called deportation, whereas the expulsion of nationals is called banishment, exile, or penal transportation. Deportation is an ancient practice: Khosrau I, Sassanid King of Persia, deported 292,000 citizens, slaves, and conquered people to the new city of Ctesiphon in 542 C.E.