During the First World War, the elimination of extraterritorial legal rights was central to the Ottoman quest for sovereignty that drove the Empire’s decision to participate in the war. The 1917 promulgation of a new Ottoman family law is recognized as a landmark moment in the history of Islamic law. Yet the 1917 law’s significance as a site of power struggles over religious jurisdiction, political power, and Ottoman sovereignty has been overlooked. Drawing on Ottoman Turkish and European sources linking internal interpretations of the law and external reactions to its passage, this paper reinterprets the adoption of the family law as a key moment in the geopolitics of the Ottoman First World War, arguing that the passage of the law was a critical turning point in the wartime process of abrogating the capitulations. Placing the law in its wartime political context and the geopolitical milieu of larger Europe, this research demonstrates that although short-lived, the 1917 family law was a centerpiece of the wartime struggle for control between the Ottoman Empire, the Great Powers, and their proxies within the Empire. Gender continues to be overlooked as a means by which statecraft has been exercised historically and as a proxy for sovereignty in non-national contexts. This analysis of the role of family law in Ottoman wartime policy is a contribution to the broader historiographical effort to understand the impact of gender and family beyond everyday practice and home life, particularly in wartime. This interpretation of the law provides a new way to locate gender at the core of the politics of sovereignty in conflict, particularly in the wartime context of radical political and social transformation that reshaped the post-war Middle East.