The analysis is aimed at examining the invisible borders that defined “otherness” in southern France in the 1920s. This involves looking at the boundaries and the collective representations that defined relations with “the other”; i.e., with foreigners and with migrants. Thie paper will also consider how “otherness” was understood and judged in this period when immigration was so important and so widely debated. My analysis of attitudes toward migrants and foreigners shows the deep complexity of these invisible borders as well as their shifting contours. Such borders did not so much oppose “the French” to “the foreign”, but functioned in such a way as to suggest a range of nuances and ambivalence.