The emergence of large fortified settlements, known as oppida, in "Celtic" Iberia during the Late Iron Age is a process which we are just beginning to understand. As in other areas of temperate Europe, there were probably substantial differences between these settlements in terms of their geographical setting, size, form, function and chronology. The exploration of the relationships between oppida, material culture and ethnicity is considered for the Vettones, one of the most famous pre-Roman peoples of western Spain. It is argued that the configuration of the settlements and communities, the sociological interpretation of the cemeteries and the regional patterns of settlement offer interesting insights into social organization of the indigenous world in Iberia between the fourth and first centuries BC.