The frontier has long been a subject of interest for historians of the Ottoman Empire, whether their focus has been on the empire’s origins, its expansion, or its efforts to assert its sovereignty as it faced the threat of European imperialism.1 Gratien’s The Unsettled Plain shows a similar interest. It examines the rationale, implementation, and legacies of various Ottoman political projects that resulted in the environmental transformation of the swampy lowlands of Çukurova in southern Anatolia into an important center of commercial agriculture from the late nineteenth to the early twentieth century. The book spans the late Ottoman period, the tumultuous years of World War I, and the formative decades of the Turkish Republic. This important contribution to the steadily growing body of work about the Ottoman frontier draws heavily from the methods of environmental history.2
For Gratien, the Ottoman frontier was not simply the sum of regions...