Focusing on Egypt, Syria, Tunisia, and Iraq, this paper asks: what explains differences in state repression among authoritarian regimes? Syria and Iraq under the presidencies of Hafez al-Assad (1971-2000) and Saddam Hussein (1979-2003) deployed highly lethal and indiscriminate violence, routinely executing political opponents. In contrast, authoritarian regimes in Egypt and Tunisia under the presidencies of Hosni Mubarak (1981-2011) and Zine el Abidine Ben Ali (1987-2011) were relatively economical in their use of violence, primarily relying on harassment, intimidation and lengthy imprisonments rather than killings. What caused these differences? Why do we observe such stark variations in levels of state repression? This paper argues that these variations have roots in different legacies of European colonial rule. Where colonial rule was introduced earlier (1880s in Egypt and Tunisia), French and British colonial rulers erected centralized coercive organizations with relatively high capacities for gathering intelligence and neutralizing threats. However, where European rule was imposed later (1920s in Syria and Iraq), external rulers did not expect to stay long, and did not invest as extensively in building local coercive institutions, relying instead on regular military units to suppress incipient nationalist movements. I propose that these different colonial experiences explain differences in the security architectures of the four countries in the latter half of the 20th century, and their varying levels of violence. In Egypt and Tunisia, European colonialism produced security forces that were more centralized, with greater capacities to penetrate society, monitor opposition, and prevent challenges from escalating, which resulted in overall lower levels of violence. In Iraq and Syria, security services were divided among agencies that were assigned over- lapping tasks; these organizations competed in recruiting informants and outbid each other in repressing dissidents. The result was repression that was less targeted, less efficient and overall much more violent.