This book examines the way securitization (and representations) of Islam and Muslims varies from one national context to another in Western Europe over the longue durée, in contrast to most literature that assumes a homogenous post-9/11 securitization of Islam in the West. Through a detailed empirical analysis of different cultural contexts (Germany, Britain, and France), both historical and comparative, this book brings to the fore differences in the relationship between religion and politics and the different philosophical underpinnings of European understandings of integration and liberalism. It also highlights how historical representations of Islam and Muslims resonate, or not, in contemporary discourses on security, thus creating a bridge between studies of imperialism, colonialism and orientalism, and critical studies of security in international relations.