In his thorough study of rural markets in northern Morocco conducted in the 1960s and 1970s, Jean-François Troin (1975) identified a commercial boundary separating exchange in the north from that in the south that ran from the midpoint between Casablanca and Rabat, south of the Zaër and Zaïan confederations, and east along the foot of the High Atlas behind Midelt. In contrast, studies of economic and social change in 19th century Morocco have focused on the differential between the burgeoning Atlantic ports and the older commercial centers of the interior. Jean-Louis Miège argued that the energy of European-driven exchange – le grand commerce – caused the ports to rival and even usurp the traditional patterns of exchange through the inland cities of Fez and Marrakech. Daniel Schroeter (1988) tempered this view by demonstrating that the port of Essaouira, the focal point of European economic activity in the sultanate, followed the rhythms of trans-Saharan caravans, regional harvests, and the religious festivals-cum-commercial fairs of Jewish and Muslim saints. By examining commercialization, patterns of exchange, and price differences in olive oil between northern and southern Morocco, I argue that the separation between northern and southern economic spheres applies to the decades before the protectorates, with important consequences for the olive growing populations of the north and the south. Drawing upon archival sources from the Biblithèque Royale and the Archives du Maroc in Rabat, I seek to demonstrate that southern Morocco's olive oil production was shaped by the export trade out of Essaouira. This encouraged elite consolidation of olive holdings and production for the export market, which in turn eroded the cohesion of tribes living in the Dir foothills of the High Atlas. In contrast, olive production in northern Morocco remained to a greater extent in the hands of smallholders who through the constellation of rural markets met the demand for oil of the northern cities and tribes of the neighboring plains, with very little of the produce going to export. We must consider how the port/interior axis of economic and social change is modified by the axis of northern and southern economic spheres in Morocco to better understand the change taking place in the late 19th century.