Historians have typically emphasized cartography and border demarcation as necessary determinants of nation and state formation in the modern era. This paper will adopt a different approach to national territoriality, arguing that Egypt and Libya emerged steadily as modern territorial nation-states in the decades before World War I despite the fact that they lacked authoritative representational practices to circumscribe the bounds of the nation. Indeed, a heightened awareness of the existence of distinctive Egyptian and Ottoman Libyan territorial spheres began to develop in this period, not through the imposition of clear-cut boundary markers or cartographic evidence, but rather through a complex interplay of local and state spatial practices that often worked at cross-purposes. As such, in this paper, I will make a special case for what I call the "lived experience of territoriality" as the conceptual lens that best enables scholars to capture the dynamic interaction between state and local actors in the forging of modern bordered political identities. Viewed this way, territoriality as it was practiced in the nineteenth century was not the sole province of state power-something that the center simply injected into the peripheries using the various administrative technologies at its disposal-but rather more of a feedback loop. Just as centralizing states were forced to adapt their territorial imperatives in light of the diversity of local spatial practices they encountered across their sovereign domains, so, too, were these various local spatial practices transformed by their encounter with modern nation-state building. The borderland that Egypt shared with Ottoman Libya presents a particularly illuminating case study for exploring territoriality in this manner. Though sparsely populated, this vast swath of the Eastern Sahara was home to a rich tapestry of local denizens, ranging from numerous pastoralist bedouin tribes, to itinerant merchants operating along the Mediterranean coast, to sedentary agricultural communities settled for centuries in the various oases dotting the desert interior. For these populations, the desert borderland was not "marginal," as it would have been seen from the seats of state authority in Cairo or Istanbul, but rather the very locus of their spatial identity. By reconstructing the multiple layers and meanings of territoriality in the Egyptian-Libyan borderland, I seek in this paper to recast the history of Egyptian nation-state formation as well as Ottoman re-centralization after the Tanzimat.