Starting with their arrival in1820’s, the restriction of religious liberties in the Ottoman Empire was the main concern for the American and British missionaries who were the most widely organized proselytizing group in the empire. On the one hand, the missionaries were enduring difficulties and harassment at the hands of local Eastern churches; on the other, the major religious group was out of their reach due to strict prohibition of proselytization among Muslims. This prohibition is based on Islamic irtidad (apostasy) principle, according to which blasphemy and renouncing the faith of Islam are crimes condemned to capital punishment. Witnessing the consequences of interpretational slipperiness when an ex-Christian convert was executed under the charges of apostasy in 1844, the legendary British ambassador to Constantinople, Stratford Canning who saved the Ottoman armies an inevitable disgraceful loss to Russia, took charge in drafting another reform edict. Islahat Fermani of 1856 clearly sanctioned the freedom of conscience for all Ottoman subjects, Muslims and non-Muslims alike, annulled legal consequences of the Apostasy principle- executions, and opened the possibility of Protestant missionary work among Muslims which produced a number of converts throughout 19th century. Utilizing the archival materials from Ottoman, British and missionary collections, I intent to unravel cases of Muslim conversion into Protestantism in the post-1856 period. Arguing against the nationalist narratives that deny any peaceful interaction between missionaries and Muslim communities, first, I will demonstrate how orthodox Sunni Muslims also opted out of Islam in their intellectual search for the “Truth.” Second, in detailing their encounter with the missionaries, attempts for registration of the apostasy and the crack down in 1865 by the state officials; I shall argue that the Muslim apostasy stood at the intersection of the local and international politics and became a litmus test for the discrepancy between the Ottoman/Islamic praxis and the new civilizational standards imposed by Western powers. Going beyond their quantitative significance, every case of apostasy received enormous attention from the diplomatic circles and missionaries alike, which triggered an official anxiety, and turned apostates into a gaze and a threat to the raison d’état in the eyes of the Ottoman officials. Third, by illustrating the changes in policies over time from official indifference to the disappearances of the converts, I will also demonstrate how the Ottoman statecraft re-defined and revealed its power through inventing and carrying out extra-judicial measures in the absence of legal sanctions against apostates.