This chapter seeks to study ethnicised physiognomical descriptions or ekphraseis of both individuals and entire population groups, primarily during the High Empire. Traditionally, physiognomical ekphraseis have been examined through the three epistemological fields where physiognomic arguments are thought to be particularly naturalised: philosophy, medical writings, and rhetoric. There is, however, at least one broad literary and ideological register that extends over and beyond these domains, yet in which physiognomising gestures are frequent: ethnographical writing. While there is no reason to regard ethnography in antiquity as a full-fledged ‘genre’ of its own, and while the term ‘ethnography’ itself was not used in ancient literature, the well-established and widely shared conventions of ancient outgroup descriptions, addressing quite distinct audience expectations, do support the view that we are dealing with a literary register that can be clearly delineated and discussed.