In 14 Octobre 1914, the French Ambassador in Istanbul informed his Minister of Foreign affairs of a panislamist pamphlet by Germany in which the German Emperor declared not to be in war against the Muslim world and ordered that all Muslims war prisoners from the French, British and Russian Empire to be released and sent to the Ottoman Sultan, in his quality of “Calif of the Mahometan world.” This message was to cause much disruption and distress for the colonial powers. Most evidently, through declaration of peace to Muslims, while the colonial empires were relying on them at the very front of the war. Moreover, by calling the Ottoman sultan the Caliph of the Muslim World, by recognizing him this title and sending him Muslim war prisoners, Germany was disrupting the fragile pillars of international law. The processes of extradition of Muslim prisoners threatened the nation-state order and its principle of citizenship, colonial subjecthood by suggesting that Muslims independently of their imperial status are subjected to the Ottoman Sultan. The German proclamations were pointing toward a transnational politico-religious order that overflows the recently erected borders of national belonging and imperial affiliation. It blasted open questions of sovereignty, by pointing toward the discrepancy between territorial sovereignty and a jurisdictional sovereignty (over people) and reopens the Pandora box of questions that follow from it: what does it mean to have sovereignty over Muslim subjects? Can a Christian empire, even when redeemed through secularization ever claim or achieve such sovereignty? How did concepts of Islamic political jurisprudence influence such debates? This paper explores, through diplomatic archives, how the colonial powers, Great Britain and France, faced the issue that territorial conquests, national borders, military power, law and violence do not guarantee the control over people sense of belonging, affiliation, allegiance and loyalism and how they sought to remedy to such a discrepancy in the postwar legal and diplomatic order. It also attends to how Muslims subjects of the empires mobilized the concepts of the Muslim world and performed their allegiance to the Ottoman empire in it their anti-colonial struggles and self-determination claims.