This chapter addresses the shift from multilingualism to monolingualism associated with the demise of the Ottoman Empire. It begins with a general overview of the linguistic conditions in the Ottoman lands, briefly surveying the historical dimensions of linguistic interactions reflecting the ebb and flow of Ottoman expansion and contraction, including the Westward movement of Turkic speakers into the central Islamicate lands and Anatolia from the eleventh century, the expansion of Ottoman rule into the Balkans from the fourteenth century, and the influx of Muslim refugees into the shrinking borders of the Empire as a result of military defeats and ethnic cleansing in the nineteenth and early twentieth centuries. The chapter then focuses on three main factors affecting linguistic interactions in the Ottoman lands: (a) the inherently multilingual nature of Ottoman Turkish as an amalgam of three languages, namely, Turkish, Arabic, and Persian; (b) the lived linguistic experience in the Empire, including the lack of a clear correlation between ethnicity, religion, and mother tongue, e.g., large numbers of Armenians, Turks, and Greeks, whose first language was not, respectively, Armenian, Turkish, or Greek, and; (c) the ways in which the advent of nationalism and Western influence affected the linguistic scene in such a diverse and demographically mixed Empire. The chapter ends by considering post-Ottoman language policies and the monolingual orientation of the modern nation-state. The tensions between the two are often revealed when signs of the multilingual past emerge to disturb the monolingual assumptions of the modern, read “national,” era.