What explains patterns of state repression during civil wars? To address this question, this paper analyzes novel data on rebel attacks and security operations during Algeria’s War of Independence from France. The data were constructed from 15,000 pages of declassified intelligence documents collected from France’s national archives, providing a uniquely fine-grained picture of violence in Algeria over time and across this territory. I find that rebel attacks targeting communes with a larger concentration of Euro-Algerians, i.e., individuals of European descent born in Algeria, elicited more violent responses from the French armed forces than similar attacks that targeted predominantly indigenous Algerian communities. These differences are not well accounted for by variations in state capacity or geography. To explain these results, I develop a new theory of bottom-up demand for repression. I argue that French forces were responsive to pressures by Euro-Algerian civilians who demanded punishment of and protection from rebel attacks against their communities, and that these civilians’ mobilization for repression helps account for variations in coercive responses. This paper contributes to literatures on colonial rule, state repression, and conflict more broadly by unpacking the processes through which civilians shape repression by armed actors.