Abstract: This dissertation examines settler fear of 'natives' and its 'unsettling' impact on decolonization in French Algeria. The work employs extensive archival research, historiographical critique, and theoretic reasoning to argue that French Algeria's so-called pieds-noirs community suffered from a longstanding colonial anxiety about the colony's Arab and Berber Muslim population, and that this anxiety shaped, strengthened, and sustained a settler experience of terror during the French-Algerian War—an emotion contributing to the character and realization of decolonization. The thesis defines and describes settler colonial fears through the colonial 'unhomely,' an elemental and central challenge to the decisive settler sentiment of being 'at home' in French Algeria. The study then identifies and articulates how settler terror affected key features of the French-Algerian War. In this way, the dissertation recasts Algerian decolonization as a process fundamentally influenced by settler fear—that is, by settler wartime terror emerging from settler colonial anxiety. The dissertation's first part works deductively to establish a settler sense of home (Chapter One) and 'unhomely' (Chapter Two) as French-Algerian realities; it then examines those realities in a single event—the Sétif Uprising (Chapter Three) and its aftermath (Chapter Four). The dissertation's second part locates setter terror in central features of the French-Algerian War. It studies terrorist tactics aimed at exacerbating settler terror (Chapter Five), a counter-revolutionary 'home guard' aimed at calming it (Chapter Six), 'ultra' movements and 'ultra' propaganda seeking to mobilize it (Chapters Seven and Eight), and repatriation statistics ultimately confirming it (Chapters Nine and Ten). The two parts share convergence as the underlying narrative gesture—moving from the early chapters' look at relatively durable structures and trends to the closing chapters' focus on pinpointed events. Settler fear drives these parallel moves and ties the two parts together—encompassing the progression toward settler colonial anxiety's dramatic revelation in 1945, and settler wartime terror's spectacular culmination in 1962.