As a scholar who witnessed his century, Sheikh al-Islam Mustafa Sabri Efendi was among the few to speak out during a period when few dared to do so regarding the "hat revolution"—a measure of the Kemalist dictatorship forced upon the people, for which many were sent to the gallows—and he exposed the true nature of the "hat revolution" as the most fanatical manifestation of the farce of imitating Westerners. Included on the list of "the 150" to be executed by the Kemalists due to his opposition, Mustafa Sabri Efendi continued his dissent uncompromisingly from far away from his homeland. In this short treatise, the late author explains the Islamic ruling on wearing a hat and examines the underlying reasons behind the hat revolution.